The Stock Exchange of Thailand climbed 0.16%, or 2.70 points, to 1,717.69 on Friday.
Total trading value was 52 billion baht, with 8.3 billion shares changed hands.
The SET50 index advanced 0.16%, or 1.81 points, to 1,113.30 in trade worth 32.3 billion baht.
MAI gained 0.32%, or 1.72 points, to 534.06 in transactions worth 2.2 billion baht.
Brokers and institutional investors were net buyers of 1 billion baht worth of shares each, followed by foreigners (657.36 million baht). Individual investors were net sellers of 2.7 billion baht.
Year-to-date, institutional investors were net buyers of 89.7 billion baht, followed by brokers (13.3 billion baht). Retail investors were net sellers of 76.8 billion baht, followed by foreigners (26.2 million baht).