It closed 19.7 points lower after losing 13.4 points on September 21.
Trading on the Ho Chi Minh Stock Exchange (HoSE), surged 40% to VND32.33 trillion ($1.33 million).
Foreign investors were net sellers for the fifth straight session to the tune of VND180 billion, mainly selling VIC and MSN.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, dropped 3.46% while the UPCoM-Index for the Unlisted Public Companies Market fell 1.76%.
