The index closed 2.62 points higher after gaining 6.50 points on Tuesday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 17.48% to VND17.20 trillion ($723.68 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 16 tickers gain.
HPG of steelmaker Hoa Phat Group went up 2.7%, followed by PDR of Phat Dat Real Estate Development with a 2.1% increase.
VCB of state-owned lender Vietcombank closed 2% higher and VIB of Vietnam International Commercial Bank increased b y1.3%.
Fourteen blue chips fell. Both SSI of leading brokerage SSI Securities Corporation and VNM of dairy giant Vinamilk lost 1.1%.
Foreign investors were net buyers to the tune of VND184.05 billion, mainly buying HPG of steelmaker Hoa Phat Group and TCM of Thanh Cong Textile Garment Investment Trading.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was down 0.40% while the UPCoM-Index at the Unlisted Public Companies Market was down by 0.14%.