Thousands of people demonstrated on Wednesday outside the Stock Exchange of Thailand (SET) to protest plans by the country's largest beer company to list its shares on the market, saying the need to make a profit would encourage drinking.
Police estimated the number of protesters at 3,000, but reporters believed it was closer to 10,000.
The demonstrators were largely members of Buddhist religious organisations, inspired by the Buddhist principle of temperance.
Many carried Thai flags, and banners with slogans such as "If you love Thailand, oppose the listing of alcoholic beverages on the SET."
A group of about 200 monks led the crowd in chanted prayers.
It occurred on the eve of one of the year's most important Buddhist holidays, Visakha Bucha.
Opponents of listing Thai Beverage PCL, the country's largest beer and liquor maker, argue that the move would be tantamount to encouraging drinking, because of the need to make a profit.
The basic principles of Buddhism, the main religion in Thailand, require followers to refrain from consuming alcohol and drugs, among other activities.
Most Buddhists in Thailand, however, do not observe the rules very strictly, and beer consumption in the country is high.
Muslims, whose religion also opposes drinking, were also among the protesters.
The company brews Beer Chang "Elephant Beer" a powerful brew that is one of the country's top sellers.
There are no beer or alcoholic drinks companies currently listed on the bourse.
A similar protest about four months ago succeeded in having the company's application suspended but it is believed it might soon be renewed.
Former Bangkok Governor Chamlong Srimuang, a long time political activist and devout Buddhist, said the protesters would submit some 63,000
signatures to Parliament later on Wednesday calling for a new law banning tobacco and alcoholic beverage companies from listing on the exchange.
Under Thailand's constitution, ordinary citizens can propose a new law if they gather at least 50,000 signatures.
Stock Exchange officials say there is currently no legal bar to the listing of an alcohol company.
The beer company hoped to raise up to 40 (b) billion baht (1.04 (b) billion US dollars through its initial public offering, which would have been the biggest in the Thai market's history.