Hong Kong’s Li Ka-shing, nicknamed “Superman” by the local media for his investing prowess, ranks second in Asia, with a $25.8 billion fortune. Lakshmi Mittal, the Indian-born chairman of ArcelorMittal, the world’s biggest steelmaker, is the third wealthiest Asian with a net worth of $23.6 billion.

Their fortunes account for about 11 percent of the combined net worth of the world’s 20 richest people. More Asians are set to dominate the ranking in the coming years after the number of billionaires in the region surpassed Europe’s in 2010 and North America’s in 2011, according to Credit Suisse Group AG.

“Asia is witnessing a tremendous economic boom now and the entrepreneurs who are steering economic prosperity are cleverly optimizing these opportunities,” said Noor Quek, previously the head of business development in Southeast Asia at Citigroup Inc.’s private-banking unit, who now runs Singapore-based family office adviser NQ International Pte. “Growth in the number and wealth of Asian billionaires will be exponential and the process has started.”

The number of billionaires in Asia rose to 351 last year, from 245 in 2010, according to the Credit Suisse Global Wealth report. Europe had 251 billionaires while North America accounted for 332 last year, the Zurich-based bank said.

No. 1 in Hong Kong

Li, Greater China’s wealthiest, ranks 12th worldwide, according to the index. His investments inCheung Kong Holdings Ltd. (1), the world’s third-largest property developer by market value,Hutchison Whampoa Ltd. (13), the billionaire’s biggest company, and Husky Energy Inc. (HSE), a Canadian oil company, are worth about $24 billion.

The 83-year-old founded Cheung Kong in the 1950s to manufacture plastics. Li increased his investments in Hong Kong real estate in 1967 after riots from China’s Cultural Revolution depressed prices. He correctly forecast in 2007 that China’s stock-market bubble would burst and predicted in 2009 the rally in Hong Kong home prices.

Mittal, named after the Hindu goddess of wealth and prosperity, is the 16th richest man in the world, according to the index.

A 47.5 percent slump in the share price of ArcelorMittal (MT) in 2011 has eroded Mittal’s fortune as cooling economies in China and Europe sapped demand for steel. His 41 percent stake in the Luxembourg-based company is worth about $14 billion, compared with about $17 billion a year ago, according to data compiled by Bloomberg.