The S&P SL20 closed 14.95 points lower at 3,272.58, down 0.45 percent.
Turnover was to 983.09 million rupees, down from 1.04 billion a day earlier, with shares of 108 firms closing in the red against 68 gainers.
Foreigners bought shares worth 492.29 million rupees, down from 544.42 million rupees a day earlier, and sold shares worth 265.30 million rupees, up from 162.51 million rupees from a day ago.
Ceylon Tobacco closed 22.90 rupees lower at 1,125.10 rupees and Carson Cumberbatch closed 14.60 rupees lower at 390.40 rupees.
JKH closed 1.10 rupees lower at 213.00 rupees and JKH Rights closed 3.30 rupees higher at 50.10 rupees.
Dialog closed 10 cents lower at 8.80 rupees and Commercial Leasing and Finance closed 10 cents lower at 4.00 rupees.
Cargills Ceylon closed 7.00 rupees higher at 157.00 rupees and Aitken Spence closed 3.20 rupees higher at 69.90 rupees.
Sri Lanka Telecom closed 50 cents higher at 39.80 rupees and Colombo Dockyard closed 8.90 rupees higher at 203.90 rupees.
Distilleries closed 1.90 rupees higher at 190.00 rupees.
Commercial Bank closed flat at 118.30 rupees.
Nations Trust Bank closed 30 cents higher at 62.00 rupees and Union Bank closed 80 cents higher at 16.70 rupees. NDB closed 80 cents higher at 154.00 rupees.
Speculative trading continued in Touchwood, closing 10 cents lower at 4.50 rupees, with more than 3.18 million shares changing hands.
PCH Holdings closed flat at 1.50 rupees with more than 1.28 million shares traded.
Access Engineering closed flat at 22.20 rupees and featured in a single crossing.
The rupee strengthened slightly to 130.70/90 against the US dollar in late trading in the spot market, after opening at 130.80/131.00 amidst low activity levels, dealers said.
A liquid five year bond was trading at 11.10 percent in late trading from 11.01/14 percent a day ago.