The index closed 6.51 points lower after losing 1.55 points on Monday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) increased by 3% to VND9.42 trillion ($401.14 milllion).
The VN-30 basket, comprising the 30 largest capped stocks, saw 27 tickers lose.
MSN of conglomerate Masan Group fell 2.7%, followed by HDB of HDBank and NVL of property developer Novaland Group, both with a 2.1% drop.
STB of Ho Chi Minh City-based lender Sacombank lost 2%, and PDR of Phat Dat Real Estate Development closed 1.9% lower.
Only two blue chips gained. HPG of steelmaker Hoa Phat Group rose 1.9% and VCB of state-owned lender Vietcombank went up 0.5%.
Foreign investors were net sellers to the tune of VND139.72 billion, mainly selling VIC of private conglomerate Vingroup and STB of Ho Chi Minh City-based lender Sacombank.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was down 1.00% while the UPCoM-Index at the Unlisted Public Companies Market was up by 0.12%.