Asian millionaires now control more wealth than those in North America, Europe and other regions, according to a report from finance firm Capgemini.
Driven by China and Japan, Asia's millionaires saw their wealth jump by 10% in 2015, the firm's World Wealth Report found.
Millionaires held nearly $60 trillion (£40 trillion) worldwide last year, four times higher than 30 years ago.
That could rise to $100 trillion by 2025, Capgemini said.
Asia's growth in high net worth individuals - defined as having $1 million in assets - came despite slowing economic growth in China and a weak Japanese economy.
Capgemini found the growth in Asia was driven mainly by financial services, technology and health care industries.
The region's millionaires held $17.4 trillion of wealth, compared with $16.6 trillion in North America, the report said.
"If past growth rates hold, Asia-Pacific is likely to continue to be a dominant force over the next decade, representing two-fifths of the world's HNWI wealth, more than that of Europe, Latin America, and the Middle East and Africa combined," Capgemini said.
Poor performance in US equity markets slowed growth in North America to 2.3% last year, although the US still had the highest number of millionaires with 4.45 million.
Europe's millionaires saw a 4.8% increase in wealth, which was led by Spain despite the country's record unemployment.
The UK had the fifth highest number of high net worth individuals, although it only increased 1% to 553,000.
Latin American millionaires suffered a decline in net worth of 3.7%, driven by political volatility and a turbulent stock market in Brazil.
Worldwide, the wealth controlled by millionaires grew 4% last year to $58.7 trillion (£39.5 trillion).
Earlier this year, Oxfam found that the richest 1% now have as much wealth as the rest of the world combined.