* Wu starts new role on Oct. 1
* China accounts for one fifth of Temasek's portfolio (Adds details)
SINGAPORE, Sept 13 (Reuters) - Singapore's state investor Temasek Holdings Pte Ltd has appointed Wu Yibing, a senior executive from China's biggest brokerage firm CITIC, to head its China business, which accounts for about a fifth of its $170 billion portfolio.
The portfolio includes significant stakes in China Construction Bank and Industrial and Commercial Bank of China .
Wu, who starts his new role on Oct. 1, will replace Ding Wei, who will become Temasek's senior advisory director for China. Ding, a former executive chairman of China International Capital Corp (CICC), joined Temasek in February 2011.
Temasek said Ding has requested to work in an advisory capacity so he can pursue other interests.
Wu is currently chairman and chief executive officer of Goldstone Investment Co Ltd, the direct investment arm of CITIC Securities, and president of CITIC Private Equity Funds Management.
CITIC Private Equity Funds is headed by one of the country's most high-profile princeling investors, Liu Lefei, the son of current politiburo standing committee member Liu Yunshan.
Wu, a fluent English speaker, is a regular panelist and keynote speaker on the private equity conference circuit in Asia.
Before joining CITIC, he was executive vice president at Legend Holdings, responsible for overall business operations. He led the firm's equity investments in the financial, energy and consumer sectors, among others.
Before that, he held various high level positions at the Lenovo Group, and prior to that he was a senior partner at McKinsey & Co. He has a PhD from Harvard University. (Reporting by Saeed Azhar and Stephen Aldred in Hong Kong; Editing by Edwina Gibbs)