The index closed 12.67 points lower after losing 0.2 points on Monday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) fell by 6.93% to VND10.45 trillion ($443.36 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 25 tickers dropped.
GVR of Vietnam Rubber Group fell the steepest with a 4.3% decline, followed by HPG of steelmaker Hoa Phat Group which went down 3.8%.
SSI of leading brokerage SSI Securities Corporation lost 3.1% and NVL of property developer Novaland Group dropped 2.7%.
Only two blue chips bucked the trend. SAB of brewer Sabeco closed 1.6% higher while VJC of budget airline Vietjet gained 1%.
Foreign investors were net buyers to the tune of VND384.98 billion, mainly buying VHM of property giant Vinhomes and SSI.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was down 1.6% while the UPCoM-Index at the Unlisted Public Companies Market was down by 0.8%.