The index closed 8.07 points lower after gaining 2.40 points in the previous session.
Trading on the Ho Chi Minh Stock Exchange increased by 16% to VND15.711 trillion (US$631.9 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 23 tickers fell.
SSB of lender SeABank saw the biggest decline of 3.6%, PLX of fuel distributor Petrolimex went down 3.3%, and VPB of private lender VPBank slid 2.4%.
Six blue chips gained. VRE of retail real estate arm Vincom Retail led with a 2.6% growth, followed by VHM of property giant Vinhomes with a 2.4% increase and GAS of state-owned Petrovietnam Gas, up 0.7%.
Foreign investors were net seller to the tune of VND768 billion, mainly selling FPT of IT giant FPT Corporation and VCB of state-owned lender Vietcombank.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, fell 0.60%, while the UPCoM-Index for the Unlisted Public Companies Market went down 0.45%.
Globally, shares across the world fell on Wednesday, pummelled by a drop in tech stocks after a record sell-off for U.S. chipmaker Nvidia and as expectations of fading global growth hit riskier assets, pushing oil prices to multi-month lows, Reuters reported.
European shares shed 1% while other major European markets from London to Frankfurt lost around 0.7%. Semiconductor companies were the biggest losers.
Wall Street closed sharply lower on Tuesday, with AI darling Nvidia inking by a record $279 billion as investors checked their enthusiasm for artificial intelligence.
Earlier, stock benchmarks in Tokyo and Taipei led the slump in Asia, each falling more than 3%, while MSCI's broadest index of Asia-Pacific shares outside Japan was last 1.9% lower.