Investor confidence for the next three months, July to September, edged up for the first time in four months on the back of expectations of fresh stimulus measures from the new government.
Confidence rose by 25.5% to 109.44 but remained in neutral territory, according to the Federation of Thai Capital Market Organisations.
An index below 80 points is considered bearish, 80-120 is neutral and over 120 is bullish.
State policies have the most effect in shoring up investment sentiment in Thailand's stock market, while geopolitical conflicts are identified as the main factor weighing on investor confidence, said Fetco chairman Paiboon Nalinthrangkurn.
Domestic political stability and the stability of the new coalition government are factors that investors are keeping a close watch on, Mr Paiboon said.
"The investor confidence index has risen for the first time in four months but is still in neutral territory for four consecutive months as well," he said. "The index gauging confidence of brokerage firms has increased from the bullish threshold to a very bullish level."
Since the bourse has risen by about 10% year-to-date, the Stock Exchange of Thailand (SET) is expected to experience a short-term correction as investors embark on profit-taking by offloading some of their equity holdings, Mr Paiboon said.
The SET index still has a positive medium- to long-term outlook, owing to anticipated fund inflows worth about 10 billion baht in the remaining months of 2019, he said, helping to boost the benchmark to 1,800 points by year-end.