UPDATE 1-Baidu 1st-qtr profit surges 71 percent

(Adds analyst estimates, details, background, stock activity)

LOS ANGELES, April 24 (Reuters) - Baidu.com Inc (BIDU.O), China's top search engine, posted better-than-expected quarterly profits on Thursday, buoyed by strong traffic growth and online advertising revenue ahead of the Beijing Olympics, sending shares up 3 percent.

First-quarter profit surged about 71 percent to 146.6 million yuan ($20.9 million) from 85.5 million yuan in the year-earlier period ended March 31.

Net earnings for the recently completed quarter were 60 cents per share, it said.

Excluding stock-based compensation expenses, profit was 67 cents per share. On that basis, the analysts' average target was 64 cents, according to Reuters Estimates.

Total revenues more than doubled to 574.4 million yuan, or $81.9 million, from 275.6 million yuan.

In China, Baidu maintains an edge over Google Inc (GOOG.O) as the most popular search engine in what some analysts say is already the world's largest Internet arena. China had 210 Internet users at the end of 2007.

Shares in Baidu rose more than 3 percent to $353 in extended trade after closing down $7.66, or 2.2 percent, to $342 on Nasdaq. ($1=6.98600 yuan) (Reporting by Lisa Baertlein and Sophie Taylor; editing by Jeffrey Benkoe)