The index closed nearly eight points lower after losing almost 37 points Monday.
VN-Index is now at the lowest since May 16.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 2 percent to VND15.77 trillion ($678.89 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 14 tickers gain.
VNM of dairy giant Vinamilk surged 6.8 percent to the highest since April 29.
BID of state-owned lender BIDV gained 2.7 percent, and TPB of private TPBank rose 2.4 percent.
Other gainers included BVH of insurance company Bao Viet Holdings, VCB of state-owned lender Vietcombank and CTG of state-owned lender VietinBank.
Twelve blue chips fell, with POW of electricity producer Petrovietnam Power Corporation plunging 7 percent.
SSI of leading brokerage SSI Securities Corporation dropped 4.7 percent to the lowest since February last year.
Foreign investors were net buyers to the tune of VND379 billion, mainly buying VNM and REE of industrial appliance maker Refrigeration Electrical Engineering Corporation.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was down 1.23 percent while the UPCoM-Index at the Unlisted Public Companies Market was down by 0.48 percent.