The index closed 4.52 points lower after dropping 3.94 points in the previous session.
Trading on the Ho Chi Minh Stock Exchange increased by 6% to VND17.214 trillion (US$676.3 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 19 tickers fell.
HDB of private lender HDBank closed 1.9% lower, CTG of state-owned lender VietinBank slid 1.7%, and BCM of Becamex Investment and Industrial Development went down 1.4%.
Seven bluechips gained. VJC of budget airline Vietjet and VPB of lender VPBank both went up 1.6% while GVR of Vietnam Rubber Group closed 1.1% higher.
Foreign investors were net seller to the tune of VND853 billion, mainly selling FPT of IT giant FPT Corporation and VHM of property developer Vinhomes.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, rose 0.29%, while the UPCoM-Index for the Unlisted Public Companies Market went down 0.26%.