He is renowned as the co-creator (with Go Nagai) of the Getter Robo anime series, as well as four of their subsequent manga continuations.
According to Nagai, he considered Ishikawa his greatest friend and ally.
Ishikawa collapsed at a dinner banquet after golfing; he was rushed to the hospital where he was pronounced dead.
Kazuki Nakashima, chief editor of the Getter Robo Saga compilation cited Ken Ishikawa as an influence when he worked on the series composition of the anime show, Gurren Lagann, and also gave a memorial address at his funeral.
An adaptation of Ishikawa's manga Gokudō Heiki was filmed as Yakuza Weapon in 2011.