BlackRock Inc., the world's largest money manager, said on Wednesday its second-quarter profit fell 11 percent as tumultuous market conditions cut into fee income.

Net income at New York-based BlackRock dropped to $554 million, or $3.08 per share, from $619 million, or $3.21 per share, a year earlier.

Investor interest in BlackRock's iShares unit, the top manager of U.S. exchange-traded funds, saved the firm from an even deeper profit decline. Investors added a net $6.1 billion into iShares funds in the quarter, while withdrawing $2.3 billion combined from BlackRock's other long-term funds.

Assets under management at June 30 totaled $3.56 trillion, down 3 percent during the quarter and down 3 percent from a year earlier.

Excluding certain expenses, BlackRock earned $3.10 per share. On that basis, analysts, on average, expected $3.01, according to Thomson Reuters I/B/E/S.

Shares of BlackRock closed down 0.5 percent to $176.15 on Tuesday on the New York Stock Exchange. The shares have lost 1 percent so far this year, trailing the 8 percent gain in the price of the Standard & Poor's 500 Index.