The meeting was also be Suu Kyi's first with a prime minister since her release from house arrest more than a year ago, National League for Democracy spokesman Nyan Win said.
Both met at the Thai ambassador's residence in Rangoon.
Suu Kyi met earlier this month with US Secretary of State Hillary Clinton. She is scheduled to meet with Japanese Foreign Minister Koichiro Gemba later this month and Britain's Foreign Secretary William Hague in January, Nyan Win said.
Asean comprises Brunei, Cambodia, Indonesia, Laos, Malaysia, Burma, Philippines, Singapore, Thailand and Vietnam.