Koesterich was earlier serving as a chief strategist at the New York-based firm’s iShares exchange-traded fund unit since 2010, according to the company as reported by Reuters.
Around 56%, or $2.1 trillion, of BlackRock’s total $3.7 trillion of asset under management are currently tied to stock and bond indexes.
In 2005, Koesterich began working at Barclays Global Investors and prior to that was chief North American strategist at State Street Corp.
Global Investors was purchased by BlackRock from British bank Barclays Plc in 2009.
BlackRock’s existing chief equity strategist Bob Doll is set to retire.