Terms of the deal, expected to close by June 30, weren't disclosed.
A spokesman for Schroders said Thirdrock's wealth management division had client assets under management of about S$3 billion ($2.2 billion) as of Dec. 31.
Thirdrock's website lists a fund management division, separate from its wealth management business, as well as corporate advisory and financial technology offerings. A spokeswoman for the firm couldn't immediately provide further details.
Thirdrock group will be merged with Schroders' existing Singapore business and operate under the Schroders wealth management brand name, the' news release said.
Jason Lai, CEO and founder of Thirdrock, will join Schroders in the new position of head of wealth management Asia, while Melvyn Yeo, chairman of Thirdrock's investment committee, will join as deputy head of wealth management Asia, the news release said.
The Thirdrock spokeswoman couldn't immediately say whether Messrs. Lai and Yeo would be replaced.