HONG KONG, June 21 (Reuters) - Asian hedge funds led global gains in May and the first five months, as bullish sentiment towards regional equities and winning positions in China boosted performance.

Asia-focused long/short funds across all strategies rose 2.8% on average in May and 7.5% during the January-May period, showing they outperformed funds that primarily invest in the United States or Europe, according to a UBS prime brokerage note this week.

In comparison, U.S. or Europe focused hedge funds were up 1% each on average in May, and 6% each for the first five months.

Driven by a surge in artificial intelligence (AI) stocks and a rebound in Chinese markets, the MSCI Asia ex-Japan index has jumped 8% so far this year and is trading at its highest since April 2022.

Japan's Nikkei is also up 15% so far this year, helped by economic recovery and corporate reforms.

UBS said the gains made by Asian hedge funds in May were "largely driven by China-focused funds", while the performance of Japan-focused funds was mixed.

Greenwoods Asset Management, one of Asia's largest hedge funds, saw its flagship fund Golden China, rise 18.3% for the year to May, and 7% in May alone, mainly on contributions from China tech and energy stocks, according to an investor letter reviewed by Reuters.

Greenwoods declined to comment.

Meanwhile, Pinpoint Asset Management's China fund jumped 11.4% in the first five months, according to a note from HSBC.

MSCI China stocks is up 23% from its January trough, and after giving up some gains in recent weeks due to weakening economic data.

For China fund managers, "if you are active and you can pick better parts versus the less good parts, you can still do a lot better than the broad index," said Timothy Moe, chief Asia Pacific strategist at Goldman Sachs.

By strategy within Asia, equity funds that bet stock prices will rise or fall, gained more than 3% last month, while quantitative and multi-strategy funds returned 2.5% and 1.3%, respectively, UBS said. It tracked 61 Asian hedge funds.

(Reporting by Summer Zhen; Editing by Vidya Ranganathan and Jacqueline Wong)