Kamen Rider Black RX is a Japanese tokusatsu superhero television series produced as part of the Kamen Rider Series. The ninth show in the franchise, it was a joint collaboration between Ishimori Productions and Toei Company, and aired on the Mainichi Broadcasting System and the Tokyo Broadcasting System from October 23, 1988 to September 24, 1989 with a total of 47 episodes. The series was a direct sequel to Kamen Rider Black and the first to feature a team-up with the past Riders since the 1984 TV special Birth of the 10th! Kamen Riders All Together!!.
The series was adapted by Saban in North America as Masked Rider. The Americanization featured a heavily altered story and all new characters, in an attempt to fit the series in as a spin-off of 'the Power Rangers series.
This was the last installment of the Kamen Rider Series to be produced in the Shōwa period and the first to be produced in the Heisei period—Episode 11 was delayed by one week following Emperor Hirohito's death.