The West Indies batsman, 33, beat Australian Andrew Symonds's 34-ball ton in 2004 and he went on to record the highest Twenty20 score of 175 not out.
Gayle smashed 17 sixes and 13 fours in a 66-ball knock, beating Brendan McCullum of New Zealand's 158 not out. His Royal Challengers Bangalore side amassed a T20 record 263-5 against Pune Warriors in the Indian Premier League.
The score eclipses the previous best of 260, set by Sri Lanka against Kenya in Johannesburg in September 2007. Gayle told ITV4: "I'm lost for words. It was just one of those days. It's a good wicket and I started well.
"I got a good total. I can't say it's a decent total - it's a good total.
"All I had for breakfast this morning was a plain omelette, two pancakes and a hot chocolate."
Pune were batting second in the match. In November last year, Gayle became the first man to hit a six off the opening ball of a Test match - the left hander hit Bangladesh debutant Sohag Gazi for a maximum in the first Test in Dhaka.