迈克尔·弗雷德·菲尔普斯二世（英语：Michael Fred Phelps II，1985年6月30日－），出生于美国马里兰州巴尔的摩市，是美国游泳运动员，绰号The Baltimore Bullet（巴尔的摩子弹）、飞鱼、水怪、水神，男子个人混合泳、蝶泳三项世界纪录的保持者。他在2004年的雅典奥运上一人拿下游泳项目上的六枚金牌，成为雅典奥运会上得到金牌数最多的运动员。2008年北京奥运，他以八面金牌的成绩打破了马克·史毕兹在1972年慕尼黑奥运所创出的七金纪录，成为在同一届奥林匹克运动会中获得最多金牌的运动员。2012年伦敦奥运会后，又成为奥运会历史上获得金牌数（18枚）及总奖牌数（18金2银2铜，共22枚）最多的运动员。

Michael Fred Phelps II (born June 30, 1985) is an American competition swimmer and the most decorated Olympian of all time, with a total of 22 medals in three Olympiads. Phelps also holds the all-time records for Olympic gold medals (18, double the second highest record holders), Olympic gold medals in individual events (11), and Olympic medals in individual events for a male (13). In winning eight gold medals at the 2008 Beijing Games, Phelps took the record away from fellow swimmer Mark Spitz (7) for the most first-place finishes at any single Olympic Games. Five of those victories were in individual events, tying the single Games record. In the 2012 Summer Olympics in London, Phelps won four golds and two silver medals, making him the most successful athlete of the Games for the third Olympics in a row.