The index closed 31 points higher after losing 29 points on Tuesday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 46.7% to VND14.37 trillion ($579.9 million), highest since October 21.
The VN-30 basket, comprising the 30 largest capped stocks, saw 26 tickers gain.
Nine blue chips hit ceiling price, including GVR of Vietnam Rubber Group, STB of Ho Chi Minh City-based lender Sacombank, BID of state-owned lender BIDV, MWG of electronics retail chain Mobile World and ACB of Asia Commercial Bank.
Other major gainers included HDB of HDBank, up 6.4%, and CTG of state-owned lender VietinBank, up 6%.
Foreign investors were net buyers to the tune of VND638.41 billion, mainly buying CTG and VHM of property giant Vinhomes.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was up 4.36% while the UPCoM-Index at the Unlisted Public Companies Market was up by 3.19%.