Richard Usher, head of spot G10 currency trading, joined the investment bank from Royal Bank of Scotland in May 2010. He is a full-time employee at JP Morgan and has not been suspended.
But he has not been at his desk for around two weeks, a source at the bank said.
Usher could not be reached for comment, and JP Morgan declined to comment.
JP Morgan, which has its European headquarters in Canary Wharf, is one of several major banks cooperating with the Financial Conduct Authority in Britain and other regulators around the world looking into allegations of manipulating benchmarks in the $5.3 trillion (£3.3 trillion) per day global foreign exchange market.