Singapore Airlines will cancel 19 flights to the Thai capital later this month due to lower demand.
The move is believed to be due to the current political turmoil in Bangkok.
The cancellations will be in force for more than a month - from January 14 to February 25.
SIA said it has informed affected customers, who will either be given refunds or put on other flights.
Travel agencies are also seeing fewer travellers to Bangkok.
Chan Brothers said there were 20 per cent fewer customers for the route last month, compared with the same period last year.
But it is still seeing bookings in the new year from travellers who are adopting a wait-and-see approach.
Jane Chang, manager of Marketing and Communications at Chan Brothers, said: "We have close to 100 travellers who will be departing for Bangkok during the Chinese New Year week despite the protests and all.
"Enquiries that will come in from our travellers are whether or not it's safe to travel to Bangkok. And what we inform (them) is that we're monitoring the situation as it is, because it's hard to tell what's going to happen during Chinese New Year right now."