Analysts say an increase in speculative trading in fundamentally weak shares could dent the healthy growth the index has seen this year.
The main stock index ended 0.42%, or 29.29 points firmer, at 7,013.32, its highest close since 18 August 2011.
The index has gained 18.61% so far this year.
“Big caps are slightly slow today the index is up on some illiquid shares and on retail activity,” said Dimantha Mathew, Manager, Research at First Capital Equities Ltd.
The index plummeted more than 20% after it hit a record peak in February 2011 mainly due to speculative trading.
Companies’ earnings were recovering and the Bourse had seen a 22% year on year net growth in earnings of 272 companies, First Capital Equities said in a note to investors.
Richard Pieris and Co Plc, which led the overall gain in the index, rose 16.67% to Rs. 9.10, while Sri Lanka Telecom Plc rose 1.11% to Rs. 54.60.
Shares in Commercial Leasing & Finance Plc rose 4.65% to Rs. 4.50.
Tuesday’s turnover stood at Rs. 1.73 billion ($ 13.3 million), more than this year’s daily average of Rs. 1.2 billion.
The Bourse saw a net foreign inflow of Rs. 480.1 million on Tuesday, extending the year-to-date net foreign inflow to Rs. 8 billion worth of shares.