The index closed 0.62 points lower after losing 27.95 points on Wednesday.
Trading on the Ho Chi Minh Stock Exchange (HoSE) fell by 5.14 percent to VND12.08 trillion ($507.03 million).
The VN-30 basket, comprising the 30 largest capped stocks, saw 11 tickers lose.
VRE of retail real estate arm Vincom Retail lost 5.7% while MSN of conglomerate Masan Group dropped 3.7%.
VJC of budget airline Vietjet fell 2.6% and HDB of HDBank went down 2.4%.
Seventeen blue chips gained, led by VIB of Vietnam International Commercial Bank with a 2.4% rise.
ACB of Asia Commercial Bank gained 2.2% and SSI of leading brokerage SSI Securities Corporation climbed up 2.1%.
Foreign investors were net sellers to the tune of VND680.64 billion, mainly selling VHM of property giant Vinhomes and VRE.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, was down 0.31% while the UPCoM-Index at the Unlisted Public Companies Market was down by 0.06%.