The Thai benchmark climbed 0.4% after the country's economy expanded at its slowest quarterly pace in a year, stirring expectations that the slower-than-expected GDP growth would open the doors for more fiscal stimulus.
Malaysian equities added 0.6%, with hospital operator IHH Healthcare rising 4% and mobile services provider Digi.com gaining 3.2%.
Other markets in the region edged down as investors awaited real evidence on U.S.-China trade deal negotiations, and as rising political unrest in Hong Kong hurt risk sentiment.
Chinese state media said that the two countries had "constructive talks" on trade over the weekend, but neither side gave details on the timing of a possible deal.
Vietnam Philippines shares dropped 0.7% each.
The Philippine index closed at its weakest level in over four weeks. Weighing on the index were conglomerate Ayala Corp which lost 0.8%, and Bank of Philippine Islands which skid 0.5%.
(Reporting by Arundhati Dutta; editing by Uttaresh.V)
By Arundhati Dutta