Thai share prices closed 0.19 percent lower on Friday on profit-taking after rising to a two-year high as softer oil prices led the key energy-linked stocks down, dealers said.
They said the losses were technical after the market added nearly two percent over the week on strong foreign investor support for the energy companies in light of soaring global oil prices.
The Stock Exchange of Thailand (SET) composite index fell 1.51 points to 773.06 and the blue chip SET 50 index declined 1.12 points to 540.57.
Losers outnumbered gainers 175 to 155, with 111 stocks unchanged on turnover of 3.0 billion shares worth 17.9 billion baht (474 million dollars).
The Thai baht still traded at a six-year high against the dollar, closing at 37.77-80 to the greenback Friday, little changed from Thursday's 37.75-77.
The Thai currency was at 46.60-66 to the euro, against 46.62-65.
"The market fell mainly due to profit-taking in the energy sector. Investors sold energy-linked shares after a fall in oil prices," said Sukit Udomsirikul, a senior market analyst at Siam City Securities.
World oil prices dipped Friday after a peak of 74 dollars a barrel amid concerns over tight US supplies and tensions over Iran's nuclear ambitions.
Shares in Thailand's top energy firm PTT fell 4.00 to 266.00 baht, but its subsidiary PTT Exploration and Production rose 4.00 to a new record 648.00.
Thai Oil, the country's largest oil refinery by capacity, fell 2.00 to 71.50.
Top lender Bangkok Bank gained 1.00 to 116.00 while the third-largest lender Kasikorn Bank was unchanged at 66.50.
Thai Airways International edged up 0.50 to 46.50.