The index stayed mostly in the red throughout the day and closed 0.03 points higher after plunging 25 points Tuesday.
Trading value on the Ho Chi Minh Stock Exchange (HoSE), on which the index is based, fell 11.6 percent to VND30.51 trillion ($1.34 billion).
Foreign investors net sold VND1.06 trillion worth of stocks, focusing on HPG of steelmaker Hoa Phat Group and VNM of dairy giant Vinamilk.
In the past three sessions their net sale value totaled VND4.04 trillion.
The VN30 basket, comprising the 30 largest capped stocks, saw 16 tickers in the red Wednesday, with BVH of insurance company Bao Viet Holdings falling 3.4 percent to a two-week low.
VRE of retail real estate arm Vincom Retail fell to a six-week low with a 2.8 percent drop.
Other losers included BID of state-owned lender BIDV and POW of electricity producer Petrovietnam Power Corporation, both fell 2.6 percent.
Thirteen blue chips gained, with PNJ of Phu Nhuan Jewelry rising 4.2 percent to new peak as gold prices repeatedly climbed to new peaks in recent weeks.
PLX of fuel distributor Petrolimex rose 2.8 percent as gasoline prices are forecast to continue rising.
Other gainers included VJC of budget airline Vietjet, up 2.2 percent, and VCB of state-owned lender Vietcombank, up 1.8 percent.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 0.29 percent, while the UPCoM-Index for the Unlisted Public Companies Market rose 0.67 percent.