BEIJING, July 17 (Xinhua) -- Global banks posted record profits from their Chinese operations last year, with many foreign lenders expecting annual growth of about 20 percent up till 2015, according to a survey released Tuesday by PricewaterhouseCoopers (PwC).

Combined net profits of 181 foreign banks more than doubled to 16.73 billion yuan (2.65 billion U.S. dollars) in 2011 from 7.78 billion yuan in 2010, boosted by multinationals' investment growth in China, according to the survey, which polled chief executives, senior managers and branch presidents of 41 foreign banks.

Assets of those foreign banks in China expanded 24 percent year-on-year to 2.15 trillion yuan last year, PwC said in the survey report.

"The fundamental challenge for the foreign banks over the next three years will be balancing the investment and needs of a dynamic and fast-developing Chinese market against the constraints of a slowing economy back home," PwC Financial Services Advisory Partner William Yung said in the report.

Since the first quarter of 2011, China's economy has slowed for six consecutive quarters, with its gross domestic product expanding only 7.6 percent in the second quarter of this year, the slowest growth pace in three years.

Foreign banks are more dedicated to their Chinese investments now than since 2008, as China continues to liberalize its currency and restrictions on its financial system, the survey found.