Affected by falling trends from Chinese mainland markets, Hang Seng Index lost its gain from last week and closed 108.06 points lower Monday.

The benchmark index opened 48.85 points lower at 20,514.83 and fluctuated between the 20,409.16 and 20,645.82 before closing 108. 06 points, or 0.53 percent lower, to end Monday's trading at 20, 455.62.

Market turnover fell to 47.852 billion HK dollars (about 6.13 billion U.S. dollars) from Friday's 50.476 billion HK dollars (6. 47 billion U.S. dollars).

HSBC, the largest stock measured by market capitalization, went down 0.42 percent to 143.1 HK dollars.

ICBC, China's largest bank, only managed to maintain its gain by going up 0.22 percent at 4.53 HK dollars.

While China Life, the largest insurance company of Chinese mainland, stopped its falling by climbing up 1.33 percent to 22.8 HK dollars.

China Mobile, the second largest stock and the country's largest mobile phone operator, went down 0.41 percent to 73.4 HK dollars.

In oil sectors, PetroChina, the country's largest oil producer, inched up 0.10 percent to 9.64 HK dollars and CNOOC, China's largest offshore oil producer, followed the trend by up 0.15 percent to 6.61 HK dollars.