The index closed 11.22 points higher after losing 0.87 points on Friday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 26.6% to VND13.79 trillion ($587.58 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 23 tickers gain.
GVR of Vietnam Rubber Group led with a 5.8% rise, followed by SSI of leading brokerage SSI Securities Corporation, up 3.8%.
TPB of private TPBank rose 2.7% and PDR of Phat Dat Real Estate Development gained 2.2%.
Only two blue chips fell. MSN of conglomerate Masan Group lost 0.6% and SAB of brewer Sabeco closed 0.1% lower.
Foreign investors were net buyers to the tune of VND125.43 billion, mainly buying KBC of industrial real estate developer Kinh Bac City and STB of Ho Chi Minh City-based lender Sacombank.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was up 1.23% while the UPCoM-Index at the Unlisted Public Companies Market was up by 0.68%.