Although Indian PM Narendra Modi invited his Pakistani counterpart to his inauguration last year, relations have deteriorated since then.
Cross-border firing along the disputed region of Kashmir have killed dozens of people from both sides.
India had initially insisted that any talks should only cover what it refers to as terrorism.
But a statement issued after Sunday`s meeting said the security advisers of the two countries had also talked about Kashmir, peace and security.
It added that Sunday`s meeting in Bangkok was held in a "candid, cordial and constructive atmosphere".
"It was agreed to carry forward the constructive engagement between the two countries," it said.
Bangkok was chosen for the venue on Sunday because it was a convenient location for both sides, an Indian foreign ministry official was quoted as saying by the Associated Press news agency.
Mr Modi and his Pakistani counterpart, Nawaz Sharif, also had an unscheduled meeting at the Paris climate change talks last week.
Indian Foreign Minister Sushma Swaraj is expected to visit Pakistan on Monday to attend a meeting on Afghanistan.
The South Asian rivals have fought two wars and a limited conflict over the disputed Kashmir region.
Pakistan has always reiterated that there cannot be any dialogue with India unless the issue of Kashmir is on the agenda.
Kashmir, claimed by both countries in its entirety, has been a flashpoint for more than 60 years. A ceasefire agreed in 2003 remains in place, but the neighbours often accuse each other of violating it.
