The CBOE Volatility Index, often referred to as Wall Street's fear gauge, slightly decreased 0.73 percent to end at 13.61 on Wednesday.

In other markets, the US dollar dropped against other major currencies as doubts over whether the Federal Reserve would raise interest rate in September increased following the sharp decline of Chinese yuan.

In late New York trading, the euro rose to $1.1162 from $1.1035 in the previous session, while the dollar bought 124.22 Japanese yen, lower than 125.15 yen of the previous session.

Oil prices bounced as traders bought the dip after prior day's sharp decline.

The West Texas Intermediate for September delivery moved up 22 cents to settle at $43.3 a barrel on the New York Mercantile Exchange, while Brent crude for September delivery increased 48 cents to close at $49.66 a barrel on the London ICE Future Exchange.

Gold futures on the COMEX division of the New York Mercantile Exchange rose on a weaker US dollar.

The most active gold contract for December delivery rose $15.9, or 1.44 percent, to settle at $1,123.60 per ounce.