The Stock Exchange of Thailand index continued its slide, while Philippine shares surged on Monday, extending their gains to a fifth straight session.
The SET index lost 9.35 points or 0.56% to close at 1,658.56, in trade worth 40 billion baht. The Thai shares fell as investor sentiment was hit after disappointing trade data for September. Exports, the key driver of its growth, fell 5.2% from a year earlier.
The Philippine index closed 1.2% higher, notching up a 4.5% gain over the last five sessions, as real-estate developer SM Prime Holdings gained after reporting a jump in quarterly earnings.
Bank stocks also boosted the Philippine market, with BDO Unibank Inc gaining 2.6% and Metropolitan Bank and Trust Co adding 4.5%.
Singapore shares edged 0.5% higher as consumer goods and industrial stocks ticked up. Wine and soda distiller Thai Beverage PCL added 3.1% and casino and gaming operator Genting Singapore Ltd rose 1.6%.
Indonesian shares traded nearly flat, as telecom stocks like Telekomunikasi Indonesia Tbk rose 1.8% and PT Indosat Tbk added 6.0 % to offset losses in the banking sector.
Meanwhile, Malaysian stocks led losses in the region, closing 0.6% lower, as telecom giant Axiata Group Bhd shed 6 % and Telekom Malaysia lost 4.2%.
"General sentiment in the Malaysian market is pretty cautious awaiting the upcoming union budget," said Nik-Ihsan, a technical analyst with Maybank Kim Eng.
The government had recently unveiled new forecasts, indicating wider fiscal deficits than earlier expected and an austere 2019 budget scheduled to be presented on Nov 2.
Rating agencies have warned its sovereign credit ratings could take a hit if the government cannot narrow its budget deficit.
Vietnamese stocks closed 0.5% lower, led by losses in financials. Joint Stock Commercial Bank for Foreign Trade of Vietnam dropped 1%, while Vietnam Prosperity Joint Stock Commercial Bank fell 2.7%.
Prime Minister Nguyen Xuan Phuc said on Monday foreign direct investment inflows into Vietnam this year would likely reach a record $18 billion.
He also said the Southeast Asian country would aim to keep the inflation rate at 4% for 2019.
However, he added there was pressure on Vietnam's inflation rate due to higher prices for crude oil and electricity as well as education and healthcare services.