The index closed 7.83 points lower after dropping 4.07 points in the previous session.
Trading on the Ho Chi Minh Stock Exchange increased by 8% to VND15.89 trillion ($655.12 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 20 tickers fell.
MSN of conglomerate Masan Group dropped 3.1%, followed by BCM of Becamex Investment and Industrial Development with a 2.7% decline.
VCB of state-owned lender Vietcombank fell 2.6% and VJC of budget airline Vietjet closed 2.2% lower.
Five blue chips gained, led by ACB of Asia Commercial Bank with a 1.1% increase.
Foreign investors were net sellers to the tune of VND1.47 trillion, mainly selling HPG of steelmaker Hoa Phat Group and MWG of electronics retail chain Mobile World.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 0.09%, while the UPCoM-Index for the Unlisted Public Companies Market went down 0.21%.