Chinese social networking site Renren Inc posted a small quarterly profit as online advertisement segment rose, but forecast third-quarter revenue largely below market expectations, sending its shares down 8 percent in aftermarket trade.

For the third quarter, Renren, dubbed as China's Facebook, expects to report revenue of $33.5-$35.5 million while analysts were expecting $35.2 million, according to Thomson Reuters I/B/E/S.

The company reported a net profit of $751,000, or break even per American Depository Share (ADS), compared with a loss of $25.5 million, or 31 cents per ADS, a year ago.

Net revenue rose 53 percent to $30.4 million, beating analysts' estimates of $29.5 million. Online advertising revenue rose 94 percent to $16.9 million.

Shares of Renren fell 58 cents in trading after the bell. The stock closed at $7.78 on Thursday on the New York Stock Exchange.