The Dodgers' $700 million superstar became the sole member of MLB's 50/50 club when he got to both marks against the Marlins in Florida.
Then to top it off, he stole another base, and let fly his third homer of the game - giving him 51/51 so far this season.
Ohtani hit his 50th homer in the seventh inning, an opposite-field, two-run shot to left against Marlins reliever Mike Baumann. One inning earlier, he hit his 49th, launching a 1-1 slider from George Soriano 438 feet to the second deck in right-center.
He took care of the stolen bases earlier in the game, swiping his 50th in the first and his 51st in the second.
The Japanese star led off the game with double against Edward Cabrera and swiped third on the front end of a double steal with Freddie Freeman, who reached on a walk.
Ohtani has been successful on his last 28 stolen base attempts.
He reached the milestone in his 150th game. Ohtani was already the sixth player in major league history and the fastest ever to reach 40 home runs and 40 stolen bases in a season, needing just 126 games.
Ohtani's previous career high in homers was 46 for the Los Angeles Angels in 2021, when he also made 23 starts on the mound and won his first of two AL MVP awards.
Manager Dave Roberts said before Thursday's game that he noticed Ohtani getting more aggressive on the bases in the second half of the season.
"I also think that Shohei realized how good of a base stealer he has become or can become," Roberts said. "I think he likes the challenge of studying pitchers and learning the tendencies. I think that's something that intrigues him."
Ohtani's previous career high for steals was 26, also in 2021. He has not pitched this season while recovering from elbow surgery, allowing him to focus his attention on batting and baserunning as the Dodgers' everyday designated hitter.