The index closed 48.53 points lower after gaining 9.64 points in the previous session.
Trading on the Ho Chi Minh Stock Exchange increased by 45% to VND23.782 trillion (US$947.4 million).
The VN-30 basket, comprising the 30 largest capped stocks, all closed in red.
GVR of Vietnam Rubber Group saw the biggest decline of 7.0%, followed by VRE of retail real estate arm Vincom Retail with a 6.4% drop and HDB of lender HDBank, down 6.1%.
Foreign investors were net seller to the tune of VND730 billion, mainly selling FPT of IT giant FPT Corporation and HPG of steelmaker Hoa Phat Group.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 3.82%, while the UPCoM-Index for the Unlisted Public Companies Market went down 3.19%.
VN-Index's plunge was in line with global developments. where multiple stock markets tumbled on Monday, with Japanese shares at one point exceeding their 1987 "Black Monday" loss, as fears of a U.S. recession sent investors fleeing from risk while wagering that rate cuts would be needed to rescue growth, Reuters reported.
Japan's benchmark Nikkei average closed 12.40% lower at 31,458.42, its largest one-day fall since October 1987, while the broader Topix lost 12.48% to 2,220.91.
European stocks opened 1.8% lower with France's CAC 40 down 2.1%, Spain's IBEX down 2.8%, and the UK's FTSE 100 off 1.7% on fears of a global recession after weak U.S. data.