Miles Edgeworth, known as Reiji Mitsurugi (Japanese: 御剣 怜侍, Hepburn: Mitsurugi Reiji) in original Japanese language versions, is a fictional prosecutor in Ace Attorney, a visual novel adventure video game series created by Japanese company Capcom. Introduced as a cold-hearted perfectionist, he is the antagonistic rival to main character Phoenix Wright in Phoenix Wright: Ace Attorney (2001). Following the events of the first game, the character has a change of heart and reappears as a friendly rival in most subsequent entries. Created by Shu Takumi and designed by Tatsurō Iwamoto, Edgeworth was more difficult for Takumi to create compared to Phoenix.

Edgeworth went on to star in two of his own spin-off games, Ace Attorney Investigations: Miles Edgeworth (2009) and its sequel; appeared in extended Ace Attorney media, such as film and animation; and made several cameo appearances in titles outside of the main Ace Attorney series. He has been generally well received by critics and fans, identified as one of the best new video game characters of the 2000s by GamesRadar+. The relationship between Phoenix and Edgeworth has also been the subject of critical commentary.

Edgeworth's first appearance was in Phoenix Wright: Ace Attorney, where he is introduced as an antagonist prosecutor with a perfect record, who would do anything to win a trial; he is presented as respectable, but cold and ruthless. Throughout the game, the perception of Edgeworth changes, starting in episode three when he, for reasons then unknown, suddenly helps Wright to corner a witness. In the next episode, Edgeworth finds himself accused of murder, and Wright defends him on detective Dick Gumshoe's request against Manfred von Karma, Edgeworth's austere adoptive father and mentor, who won every case in his 40-year prosecutorial career. It is revealed during this episode that Wright and Edgeworth, along with Larry Butz, were childhood friends, and that Manfred von Karma murdered Miles's father, the defense attorney Gregory Edgeworth, and raised Miles as a prosecutor under his wing as revenge for a minor penalty tarnishing his otherwise spotless record. Edgeworth blamed himself for his father's death, a fact that led to him becoming a prosecutor instead of a defense attorney. In "Rise from the Ashes", a fifth episode included in all subsequent editions of Phoenix Wright: Ace Attorney, he is plagued by rumors about his past as a prosecutor, abandoning his job and disappearing. He returns in Phoenix Wright: Ace Attorney – Justice for All, having figured out what it means to be a prosecutor. He assists Phoenix and his adoptive sister, Franziska von Karma, the prosecutor of that game in taking down the final villain of the game. He appears again in Phoenix Wright: Ace Attorney – Trials and Tribulations in Phoenix's place on his request when Phoenix becomes incapacitated. The game also shows Edgeworth's first case as a prosecutor, where he faces off against Mia Fey.

Edgeworth gained a starring role in the spin-off Ace Attorney Investigations: Miles Edgeworth, in which he investigates murders relating to a smuggling ring. During the course of the game, he meets Kay Faraday, a young self-proclaimed "great thief", who acts as his assistant in a similar vein to Maya. A flashback case focuses on a younger Edgeworth investigating a case early in his career, explaining how he and Detective Dick Gumshoe first met. In Ace Attorney Investigations 2: Prosecutor's Gambit, Edgeworth comes under fire by the Committee for Prosecutorial Excellence, who seek to have him stripped of his badge. Edgeworth begins investigating cases tied to a larger conspiracy and cover-up, including the last case his father took before his murder, and struggles between his life path of becoming a defense attorney like his father, or continuing as a prosecutor.

Edgeworth returns as a friendly rival in Phoenix Wright: Ace Attorney – Dual Destinies and Phoenix Wright: Ace Attorney – Spirit of Justice, with Dual Destinies set eight years after Trials and Tribulations. Now promoted to Chief Prosecutor, Edgeworth assists Phoenix in solving mysteries in each game and serves as a prosecutor in a limited capacity, filling in for Simon Blackquill and Nahyuta Sahdmadhi respectively.

Edgeworth has appeared in other media adaptations of Ace Attorney. In the Japanese Ace Attorney stage musical Ace Attorney – Truth Resurrected, staged by the all-female troupe Takarazuka Revue, Asahi Miwa portrays Leona Clyde, an original composite character based on Edgeworth and Lana Skye, depicted as Phoenix Wright's love interest, who defended him in his childhood class trial as a young girl in place of Edgeworth. While Edgeworth is also present in the musical and its sequel Ace Attorney 2 – Truth Resurrected, Again (in which Leona is established to have died) as a separate minor character, respectively portrayed in each by Hikaru Nanaho and Hiro Yūmi, he is merely a rival to Wright with no personal connection to him.

Takumi Saito portrays Edgeworth in the 2012 live-action film Ace Attorney, loosely adapting his role in the first game; Roi Hayashi plays Edgeworth as a child. Edgeworth appears in the 2016 Ace Attorney anime series, which adapts the events of the first three games in the series; he is voiced by Masashi Tamaki [ja] in Japanese and Christopher Wehkamp in English. Edgeworth also appears as a recurring character in the Phoenix Wright: Ace Attorney manga series, as well as the main character of its spinoff series, Ace Attorney Investigations: Miles Edgeworth.

Miles Edgeworth makes a brief cameo in She-Hulk's ending cutscene in Ultimate Marvel vs. Capcom 3, in which Phoenix Wright is a playable character.