06 percent (2.74 points) to close at 4,517.74.
Turnover was 1.1 billion rupees, according to stock exchange provisional figures.
Analysts said the market price-to-earnings ratio, based on the trailing earnings per share for the past 12 months, had reached 19.
5 times and would continue to rise and be cushioned by healthy corporate earnings in 2010.
"The post-election high investor sentiment remained throughout the week as we approach the March earnings season," Nikita Tissera, research manager at stock brokering firm SC Securities said.
"We have revised our earnings forecasts for a majority of our coverage for the 2010 financial year but we feel the corporate sector will feel the real benefits of peace from 2011 onwards.
"
The markets were closed Tuesday and Wednesday because of traditional New Year festivities which followed last week's parliamentary polls won by the ruling alliance.
John Keells Hotels, a unit of conglomerate John Keells Holdings (JKH) closed at 20.
25 rupees, up 1.25 with over 13 million shares changing hands, while Aitken Spence Hotel Holdings closed at 448.00 rupees, up 3.50, brokers said.
JKH which also has business interest in transport, retail, food processing and financial services closed flat at 190.00 rupees.
CW Mackie group closed at 45.75 rupees, up 4.00 with 823,000 shares traded, brokers said.
Brokers said in a privately negotiated off-the-floor deal 200,000 National Development Bank shares changed hands at 220.00 rupees. It closed at 220.00 rupees, down 3.00.
Commercial Bank of Ceylon closed flat at 234.00 rupees, Hatton National Bank closed at 212.
00 rupees, down 2.50, Sampath Bank closed at 238.
25 rupees, up 3.25 and Seylan Bank closed at 51.
00 rupees, up 50 cents.
Lanka Securities said in a report the benchmark All Share Price Index ended the week up 27.
25 points while the more sensitive MPI lost 7.
25 points.
Foreign participation in market activity was 26.
8 percent with a net foreign outflow of 342.6 million rupees during the week.