Kamen Rider Blade the Movie: Missing Ace (劇場版 仮面ライダー剣 MISSING ACE, Gekijōban Kamen Raidā Bureido Misshingu Ēsu) is the theatrical superhero film adaptation of the Japanese 2004 Kamen Rider series, Kamen Rider Blade, directed by Hidenori Ishida and Katsuya Watanabe and written by Toshiki Inoue.

The film is produced by Ishimori Productions and Toei, the producers of all the previous television series and films of the Kamen Rider series. Following the tradition of all Heisei Kamen Rider movies, it is a double bill with the movie for 2004's Super Sentai series Tokusou Sentai Dekaranger, Tokusou Sentai Dekaranger The Movie: Full Blast Action, both of which premiered on September 11, 2004. The film's title is translated into English as Masked Rider Blade The Movie: Missing Ace.

The Director's Cut was released on DVD on May 21, 2005, and peaked at number 13 in the weekly Oricon chart, remaining in the list for 5 weeks. A Blu-Ray reissue of the movie was released on June 13, 2010.