The index closed 9.56 points higher after losing 5.06 points on Tuesday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 46.71% to VND9.86 trillion ($417.31 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 25 tickers gain.
VPB of private lender VPBank led with a 3% rise, followed by ACB of Asia Commercial Bank, up 2.9%.
PDR of Phat Dat Real Estate Development went up 2.8% and GVR of Vietnam Rubber Group rose 2.5%.
Four blue chips dropped, with NVL of property developer Novaland Group plunging 6.7%.
STB of Ho Chi Minh City-based lender Sacombank fell 4.3% and VHM of property giant Vinhomes was down 0.6%.
Foreign investors were net sellers to the tune of VND329.59 billion, mainly selling STB and NVL.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was up 1.52% while the UPCoM-Index at the Unlisted Public Companies Market was up by 1.96%.