This article is about a/an rider in the film Kamen Rider J.
Kamen Rider J
Kouji Segawa
Gender: Male
Series: Kamen Rider J
Motif: Grasshopper
Rider Type: Protagonist
Homeworld: Earth (Main Timeline Continuity)
First Appearance: Kamen Rider J
Last Appearance: Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai
Number of Episode
7 (movies)
Actor: [[Yūta Mochizuki
Kouta Nemoto (All Riders vs. Dai-Shocker, Decade: Final Chapter)
Tetsu Inada (Kamen Rider Taisen)]]
Kamen Rider J
Kamen Rider J

Kouji Segawa (瀬川 耕司 Segawa Kōji?) is Kamen Rider J (仮面ライダーJ Kamen Raidā Jei?), the main protagonist in the Japanese tokusatsu movie Kamen Rider J.


Kouji is an environmentalist reporter who was investigating the pollution by the lake. He was killed while attempting to protect his young friend, Kana and was thrown over the cliff by the Fog Mother's child Agito as Kana is taken by the insectoid Zu. However, Kouji was resurrected by the Earth Spirits as a J-Powered Warrior, Kamen Rider J, acting on their will to fight the Fog with their emissary Berry as his guide. With Fog Mother sensing Kouji's presence, Agito attempts to finish the job in his true form, only to be killed by J. Hurrying to Kana, Kouji enters their domain and faces Zu as she assumes her true form. Facing her, J manages to mortally wound Zu as she grabs him, taking to before they crash into the fortress which is Fog Mother.

After she dies, Kouji learns of Fog's intention of feeding humanity to Fog Mother's brood as Garai completes the ritual and sends Kana to the hatching chamber while manhandling Kouji. Berry intervenes to free Kana from Fog's spell before being struck down by Garai as Kana is sent down to her death while Fog Mother begins attacking a nearby city to prepare for her children's awakening. Assuming his Rider form, J fights Garai in his true form, Cobra Man, in a heated battle. After killing Garai, J is being digested by Fog Mother as he attempts to save Kana. However, absorbing the life energy around him, J kills off Fog's newly born spawn as he escapes the bowels of Fog Mother and assumes Jumbo Formation. After ripping Kana out of Fog Mother, J battles the monster before killing her as she attempted to take him down with her. Escaping Fog Mother's destruction, Kouji takes Kana to a serene environment with Berry watching from a distance.

Later Appearances in Kamen Rider/Super Sentai live action productionsEdit

Kamen Rider WorldEdit

ZO and J, with Berry

ZO and J, with Berry.

Later, J teamed up with Kamen Rider ZO. The two riders fought a gang of five revived monsters led by Shadow Moon: Sai Mutant, Cyborg Soldier Lv. 2, Agito, Garai, and Zu. Berry witnessed Shadow Moon's plot and is attacked by the mutants. Masato and his sister Ayumi stumble onto an injured Berry by chance and are chased by the revived mutant army as a result.

However, they are saved by the sudden arrival of Kamen Rider ZO on his ZO Bringer motorcycle, who thwarts off the monsters into a nearby abandoned warehouse. ZO is suddenly assisted by Kamen Rider J, who arrives into the warehouse on his J Crosser bike. The five mutants are defeated by the combined forces of the new Double Riders. The two are then challenged by Shadow Moon, who enlarges himself into giant proportions. J grows into giant size as well and fights off Shadow Moon by himself. Shadow Moon is defeated and peace returns to the day. Kamen Rider World

Decade: Final ChapterEdit

He fought Tsukasa (Kamen Rider Decade Violent Emotion) in Jumbo form, but was defeated when Decade used The Side Basshar & G4's Gigant Kamen Ride Cards bombarding him with a barrage of missiles and sealed him in a Kamen Ride Card. J was depicted as slow moving in Jumbo Formation and unable to land a hit against the card wielding Kamen Rider.

Let's Go Kamen RidersEdit

J (Let's Go Kamen Riders)

J as seen in Let's Go Kamen Riders.

A mishap caused by the Greeed Ankh unintentionally altered the timeline which enabled Shocker to utilize a Cell Medal to create the Shocker Greeed which defeated the Double Riders and seemingly erased the legacy of the Kamen Riders from history. In 2011, after Kamen Rider New Den-O's attempt to repair the damage, he along with Kamen Rider OOO and M-Ankh awaited execution. However, it was revealed the Double Riders had their brainwashing removed by a Shocker scientist.

The Double Riders joined with New Den-O and OOO to fight Shocker's forces, but were eventually defeated. When the order was given to kill everyone, V3 suddenly appeared, asserting that there were more than four riders. V3 was soon followed by all the other revived riders that came after him, including J, as even though Rider history was changed, the people's memories haven't changed.

After the riders were united, they faced off against Shocker's Great Leader. Later, when joined by a force of extra riders, J and all the other riders got on their motorcycles and performed the "All Rider Break", ramming into the Rock Great Leader and defeating it once and for all. OOO, Den-O, All Riders: Let's Go Kamen Riders

Super Hero TaisenEdit

14 Showa KR,9 Heisei Rider & 1 Neo-Heisei Rider(with Accel)

J was among the Kamen Riders caught up in the 'Super Hero Taisen' incident. He was presumably sent to the dimensional rift, under the pretense of being defeated, by Captain Marvelous while he was apparently hunting the Riders. When his and Tsukasa's ruse was revealed, J and the other Riders appeared through the dimensional wall. J then fought alongside all the other Kamen Riders and Super Sentai against Dai-Shocker and Dai-Zangyack's Shocker-Zangyack Alliance. Kamen Rider × Super Sentai: Super Hero Taisen

Kamen Rider TaisenEdit

J vs gaim suika

J vs Gaim Suika Arms

J, in Jumbo Formation was seen fighting Fourze in Rocket States after he defeated Skyrider, and defeats the space Rider with a Jumbo Rider Punch when the latter tried to hit him with a Rider Double Rocket Drill Kick. After Fourze is defeated, he would later engage Gaim in Orange Arms, who then assumed Suika Arms Gyro Mode as he jumped off his shoulder after running up the enlarged Rider to properly fight J, with the smaller Rider proved to be more than a perfect counter to J. J was then defeated by Yoroi Mode skewering his Suika Sojinto hard into his chest, turning him into a Lockseed. Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai


Kamen Rider J

Kamen Rider J

Kamen Rider J's primary form. In this form, Kamen Rider J has the ability to execute the J-Kick.

Appearances: Kamen Rider J, Kamen Rider World, Let's Go Kamen Riders, Super Hero Taisen, Kamen Rider Taisen


Giant Kamen Rider J

By harnessing the lifeforce from the surrounding life forms, Kamen Rider J can grow into a giant size at 40 meters tall (the largest size he has used) to fight against larger opponents. In this form, Kamen Rider J has the ability to execute the Jumbo Rider Kick.

Appearances: Kamen Rider J, Kamen Rider World, All Riders vs. Dai-Shocker, Decade: The Last Story, Kamen Rider Taisen



J spirit henshin belt

J-Spirit transformation belt.

Main article: J-Spirit

The J-Spirit (Jスピリット Jei Supiritto?) is Kamen Rider J's transformation belt.




Main article: J-Crosser

The J-Crosser is a Suzuki off-road bike that Kamen Rider J rides on. It has the ability to reach a speeds up to 1300 km/h (807 mph). Kamen Rider J also can use the J-Crosser to execute the J Striker attack.

Legend Rider DevicesEdit

Kamen Ride J

Kamen Ride J

Kamen Ride J (カメンライドJ Kamen Raido Jei?) is the Kamen Ride Card which contains the power of Kamen Rider J. Used by Diend to summon Kamen Rider J in Jumbo Formation. Used in the World of Decade to fight King Dark.

In All Riders vs. Dai-Shocker, Decade Complete Form Jumbo Formation performed the Final Dimension Kick, a variation of the Dimension Kick, transforming the Shōwa Riders, including J, and Heisei Riders into Kamen Ride cards for Decade to travel through as opposed to Final Attack Ride cards before hitting the target.

In Kamen Rider × Kamen Rider W & Decade: Movie War 2010, Decade acquires Kamen Ride Cards for all of the Kamen Riders he defeats, including J, Skyrider, and Super-1.

J LockSeed

J Lockseed

Kamen Rider J Lockseed (仮面ライダーJロックシード Kamen Raidā Jei Rokkushīdo?): A Lockseed bearing the likeness of Kamen Rider J, created when J was defeated in the battle between the Showa Riders and Heisei Riders. Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai The core image depicts J's waist while the lid backside image depicts Berry. When inserted into a Sengoku Driver or when channeled through the Showa Rider Lockseed, it would allow an Armored Rider to assume J Arms (Jアームズ Jei Āmuzu?). It is styled for Gaim, Kurokage, Bujin Gaim, and Kamuro in the toyline.

  • Transformation: J Arms: Shingeki Jumbo Formation!
    • Squash: J-Kick (Jキック Jei Kikku?)
    • Au Lait: J-Crosser (ジェイクロッサー Jei Kurossā?)
    • Sparking: Jumbo Rider Kick (ジャンボライダーキック Janbo Raidā Kikku?)

Other AppearancesEdit

Although Yūta Mochizuki has never returned to portray the character Kouji Segawa, the "Kamen Rider J" character has appeared in later Kamen Rider/Super Sentai live action productions.

Kakuranger Stage Show at Super Hero Korakuen YuenchiEdit

In a stage show where the Kakurangers are seen fighting their usual foes, the Bandora gang, the Gorma tribe, and Fog show up and end up defeating them. Kamen Rider J, RyuuRanger, HououRanger, TyrannoRanger, & DragonRanger arrive to assist the Kakurangers.

Video GamesEdit

  • Kamen Rider J is a playable character in the 2011 Nintendo DS video game All Kamen Rider: Rider Generation and Rider Generation 2 for the Nintendo DS and Sony PSP.

Kamen Rider Battle: GanbarideEdit

"To be added"

Behind the scenesEdit


Kouji Segawa was portrayed by Yūta Mochizuki (望月 祐多 Mochizuki Yūta?). As Kamen Rider J, his suit actor was Jiro Okamoto (岡元 次郎 Okamoto Jirō?).

Rider No.Edit

As the leading Rider protagonist of Kamen Rider J, Kouji Segawa (Kamen Rider J) is labeled Kamen Rider #15 (仮面ライダー15号 Kamen Raidā Jūgogō?) and Showa Rider #15 (昭和ライダー15号 Shōwa Raidā Jūgogō?). Quiz! Decade Countdown!!


  • Yuta Mochizuki, who played Kouji Segawa, also played Yamato Tribe Prince GekiIcon-crosswiki, one of the protagonists from Kyōryū Sentai ZyurangerIcon-crosswiki.
  • Interestingly, Kamen Rider J closely resembles Kamen Rider ZO.
    • This is because the producer of the two films wanted the two to be the new Double Riders.
      • This was mentioned by Kamen Rider ZO himself in the 4th episode of the Lets Go Kamen Rider Net Movies, where he complained that everyone mistakes him for J when they are in a scene together.
  • Kamen Rider J's ability, Jumbo Formation closely resembles Ultraman, the difference is when Ultraman changes he automatically transforms into a giant. Another difference is Ultraman is powered by light and can only fight for a short period of time, while J is powered by the life energy of the Earth and can fight for as long as he wants in Jumbo Formation.
  • Kamen Rider J is considered by fans to be the last of the Showa Era Riders due to Shotaro Ishinomori's death in 1998, despite the official Showa Era ending in 1989 with the death of Emperor Hirohito. Toei eventually adopted this same classification in the 2014 film Heisei Rider vs. Showa Rider: Kamen Rider Taisen feat. Super Sentai out of respect to the creator of the franchise as well as the fans. All future Riders would be classified as Heisei Riders due to them being created without Ishinomori's involvement.


Also seeEdit