Singapore-based Remy Klammers, a high-profile hire from Lehman Brothers back in 2008, is expected to begin his own startup, two sources with knowledge of the move said.
A bank spokesman confirmed Klammers' departure and said his last day was November 18, but did not provide details such as why he left.
The Asia-focussed bank, unlike some of its Western peers, has navigated the financial crisis well so far, with its income expected to grow by at least 10 percent this year.
StanChart's operating profit before tax in the first nine months grew at a double-digit rate, helped by a strong performance in key markets such as Hong Kong and Singapore, it said in an update on its business earlier this month.
But many of its rivals have embarked on job cuts, laying off staff in fixed-income, derivatives and even equities in Asia, hit by slump in trading income and dealmaking.
Klammers was part of a team led by Lenny Feder, the ex-Bear Stearns executive who joined StanChart in July 2007 to reorganise the UK bank's financial markets unit.
Klammers' mandate was to build a business that involved areas such as trading and quants, which involves the use of complex mathematical formulas.
He previously worked at Lehman in Tokyo as head of structured products for Asia, and had also been at Goldman Sachs and BNP Paribas before.
Many of StanChart's global business heads are based in Singapore.
(Editing by Kevin Lim)