Kolkata, Nov 13 (BBC) : His 264 in the fourth ODI against Sri Lanka beat the previous world record of 219 made by fellow Indian Virender Sehwag against West Indies in 2011.
The right-hander also became only the second man to hit two double centuries in ODIs.
The opener's 173-ball knock included 32 fours and nine sixes and carried the home side to 404-5 in Kolkata.
"I'm not really tired, I was ready to bat another 50 overs," said Rohit. "Once I got to 50, I knew I had to convert because it was a good batting wicket.
"We wanted to get a big score and that made me stay there as long as possible.
"Kolkata is a very special ground to me, I made my first-class debut and Test debut here. I also got an IPL hundred here, so it's very special."
Before 2010, no batsman had passed 200 in 2,961 previous one-day internationals, but Rohit's effort is the fourth 200 in four years, all of which have been made by India batsmen in India.
Sachin Tendulkar became the first man to reach 200 against South Africa, with Sehwag beating that record a year later.
Since then, Sharma made his first double hundred, 209 against Australia at Bangalore.
The highest ODI score by an England batsman is the unbeaten 167 by Robin Smith against Australia at Edgbaston in 1993. Since that was set, every Test-playing nation except for Bangladesh has had a batsman hit a higher individual ODI score.
Rohit's new record came in his first international innings since August because of a finger injury.
Taking advantage of some sloppy Sri Lanka bowling and fielding - he was dropped three times, including twice after passing 200 - Rohit drove through the covers, hit four straight sixes and five over the leg side.
His third fifty came from only 25 balls, his fourth from 26 and his fifth from only 15, while, in a fifth-wicket stand of 128, Robin Uthappa contributed just 16.
India captain MS Dhoni, not playing in the match, tweeted: Very well batted Rohit. That's Rohit for everyone, sheer talent. Enjoy and witness the class in action."
India have already have an unassailable 3-0 lead in the five-match series, against a Sri Lanka side who would not have been taking part had West Indies not abandoned their tour in October.
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