The 79-year-old Li (pictured here) is the chairman of Cheung Kong Holdings Limited and Hutchison Whampoa Limited, a conglomerate with 250,000 employees worldwide. His businesses are especially tied to Hong Kong, where he has massive investments in telecommunications, real estate, electricity, retail, shipping and the Internet.

According to sources, Li is not making the investment in Facebook via the companies he controls, but through another investment entity. He also has the right to invest another $60 million in Facebook.

Li has plenty of cash to do that–he is considered the richest man in Asia and was named the ninth richest person in the world by Forbes last March, with wealth valued at $23 billion.

He built that fortune from humble beginnings–his family fled mainland China when he was a boy. Li, who dropped out of school at 15 after the death of his father, started his career as a worker-laborer in a plastics company.

Facebook, according to sources, is still planning on raising more investment dollars, although some once-hot prospects, such as Providence Equity Partners, have dropped out due to the onerous terms Facebook has demanded from investors.

While both Microsoft and Li have agreed, for example, Providence was put off by the lack of downside protection and also the fact that a major investment in Facebook would not get them a seat on the board of the start-up. Neither Microsoft nor Li will get a Facebook board seat.

The deal with Li came through a Facebook investor, who introduced the company to Solina Chau, director of the Li Ka-shing Foundation. Chau is also a major stockholder in Tom.com, a media company in China in which Li’s companies also have an interest. His investment might give Tom a leg up in possible partnerships with Facebook in China, said sources.