The index started off in the green but began to fall at around 10 a.m. before closing with a near 18-point drop. This is its fourth losing session in the past five sessions, sending it to the lowest level since May 20.
Trading value on the Ho Chi Minh Stock Exchange (HoSE), on which the index is based, remained low at VND19.3 trillion ($834.64 million) as investors continued to observe the market. The bourse saw 234 tickers lose and 138 gain.
The VN30 basket, comprising the 30 largest capped stocks was dominated by red with 22 tickers losing, led by TCB of largest private lender Techcombank with a 5.4 percent drop.
Other major banking tickers that fell included TPB of private TPBank, down 5.2 percent, STB of HCMC-based lender Sacombank, down 4.5 percent, and VPB of private lender VPBank, down 3.9 percent.
MWG of electronics retail chain Mobile World fell 4.9 percent to the lowest in the last five sessions.
PNJ of Phu Nhuan Jewelry dropped 3.2 percent. This is its fifth losing session in a row.
Six tickers managed to buck the end, led by KDH of real estate firm Khang Dien House and VRE of retail real estate arm Vincom Retail, both up 1.4 percent.
Foreign investors took the opportunity to buy with a net value of VND327 billion, with strongest pressure on HPG of steelmaker Hoa Phat Group and VHM of real estate giant Vinhomes.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 0.67 percent, while the UPCoM-Index for the Unlisted Public Companies Market dropped 0.94 percent.