The index closed 22.83 points lower after dropping 10.14 points in the previous session.
Trading on the Ho Chi Minh Stock Exchange decreased by 14% to VND18.07 trillion ($712 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 24 tickers fell.
GVR of Vietnam Rubber Group dropped 6.6%, followed by MBB of lender MB with a 5.2% decline.
TPB of private TPBank fell 4.6% and POW of electricity producer Petrovietnam Power Corporation closed 4.5% lower.
Five blue chips gained, led by SSB of SeABank with a 1.4% rise.
Foreign investors were net sellers to the tune of VND124 billion, mainly selling FPT of IT giant FPT Corporation and VNM of dairy giant Vinamilk.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 1.59%, while the UPCoM-Index for the Unlisted Public Companies Market went down 1.31%.