Sources close to the deal told Bloomberg that the team, which will be led by the former head of Lehman's electronic trading arm in the region, Anthony Brooker, will offer electronic equities trading systems and products to hedge funds and institutional investors.
The appointments are part of Mizuho's strategy to develop a Asian equity trading business to rival that of Nomura Holdings, the site added.
Nomura had previously agreed to purchase Lehman's Asian, Middle East and European divisions following the collapse of the Wall Street bank in September. Around 8,000 staff transferred to the company under the deal.
However, over 100 ex-Lehman employees, including Mr Brooker, preferred to seek work elsewhere rather than join Nomura.
Makoto Haga of Tokyo hedge fund Wing Asset Management told Bloomberg: "It's positive to see Mizuho expanding its commission business, as it can't make much money from lending or investment banking."
Established in 2003, Mizuho currently employs around 265 staff.