Ken Kogashiwa (小柏 健 Kogashiwa Ken) is Kai's father and Bunta's lifelong rival when Bunta was still racing with the AE86 Trueno. Ken was defeated multiple times by Bunta, and it still seems to be a sore spot for him.

After couple of years of not racing against his undefeatable opponent. He was told by his son that Kai witnessed a similar AE86 drifting aside from his car. Kai thought that it was supposed to be Bunta passing by. However, when the secret was revealed, Bunta lied to him that Takumi was actually delivering with his AE86 even though it wasn't Takumi after all. Ken then scheduled the race between his son and Takumi and told Kai to use his special technique to tackle against corners more efficiently. Depressingly to mention, his son didn't manage to win although he followed his father's orders.

Age 40+ (possibly similar to Bunta)
Sex Male
Car Toyota MR2 G-Limited (SW20)
Year 1996
Color Same as Kai Kogashiwa
Plate Same as Kai Kogashiwa
Custom Parts Same as Kai Kogashiwa
Japanese voice actor Kinryu Arimoto
English voice actor Bruce Carey