BEIJING, July 24 (Xinhua) -- Baidu.com, China's search engine portal, said Friday its second quarter profit surged 53 percent year on year to 422.8 million yuan (62.18 million U.S. dollars) back by active online marketing.

    Its sales revenue hit 1.1 billion yuan in the same period, up 36.7 percent year on year, the company said after it provided online marketing service to 203,000 customers, up 12.2 percent from a year ago.

    The profit increase is driven by continuous technology improvements to meet customer's varied demands, said Robin Li, the chief executive officer of the company.

    The Beijing-based company expected the third-quarter profit will grow by 15 perent to 18 percent from the second quarter.

    China has the world's biggest population of Internet users, with 338 million people online by the end of June.