Qian replaces David Li, who left the firm in September last year, a spokesman said.
Qian has 20 years of experience in China/Hong Kong banking and worked as president and board director of Citi China.
At Citi, he was responsible for corporate and investment banking strategy as well as the consumer banking businesses. He joined Citi in 2007 and held a number of senior roles, including head of China corporate & investment banking and co-head of China investment banking.
Qian worked with UBS's investment banking division in Hong Kong from 1996 until 2003. He has also worked with Deutsche Bank.
Meanwhile, the firm also said it has appointed Di He as chairman of the board of UBS Securities Company in China.
"With their exceptional experience and knowledge, I am confident they (Qian and He) will expand our leadership position in the investment bank in China, and provide momentum to further build our wealth and asset management businesses," said Chi-Won Yoon, UBS president Asia Pacific.
Both Qian and He report to Yoon.
China is one of the most important markets for UBS globally, the firm said, adding it invested early in the country and has built a multi-entity domestic platform.