The index struggled to surpass the 1,370 range and started falling in the afternoon. It closed with a 5-point drop after rising over 21 points in the previous two sessions.
Trade value on the Ho Chi Minh Stock Exchange (HoSE), on which the index is based, fell nearly 5 percent to VND22.65 trillion ($983 million). The bourse saw 173 tickers gain and 232 lose.
Foreign investors were net sellers to the tune of VND1.09 trillion, the highest since June 4, with strongest pressure on NVL of real estate developer Novaland Group and HPG of steelmaker Hoa Phat Group.
The VN30 basket, comprising the 30 largest capped stocks, saw 17 tickers in the red, led by SSI of leading brokerage SSI Securities Corporation, down 3 percent.
The ticker has lost 5.8 percent from its peak last week.
TCH of real estate company Hoang Huy Investment Financial Services fell 3 percent to a near 4-week low.
BID of state-owned lender BIDV fell 2.5 percent, having lost over 8 percent since achieving a new peak earlier this month.
REE of industrial appliance maker Refrigeration Electrical Engineering Corporation lost 2.5 percent, while SBT of sugar producer Thanh Thanh Cong – Bien Hoa JSC fell 2.2 percent.
Ten blue chip tickers bucked the trend led by NVL, up 5.8 percent, followed by PLX of fuel distributor Petrolimex, up 3.7 percent.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 0.78 percent while the UPCoM-Index for the Unlisted Public Companies Market dropped 0.57 percent.