The main stock index rose 0.16 percent, or 9.29 points, to close at 5,787.81. It added 3.87 billion rupees ($29.6 million) in market value.
The day's turnover was 179.9 million rupees, its lowest since Dec. 24, 2012 and well below this year's daily average turnover of 840.3 million rupees.
Shares in Ceylon Tobacco rose 3 percent to 1,139.50 rupees, while Nestle Lanka rose 2.14 percent to 2,150 rupees.
Foreign investors were net buyers of 23.5 million rupees worth of shares on Wednesday, extending their net buying to 23.14 billion rupees so far this year.
($1 = 130.8000 Sri Lanka rupees)
(Reporting by Ranga Sirilal; Editing by Prateek Chatterjee)
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