The index went sideways most of the day before surging to break the 1,180-point mark in the afternoon, but quickly dropped thereafter, closing just 2.6 points up.
Trading volume on the Ho Chi Minh City Stock Exchange (HoSE), on which the index is based, moved up 0.6 percent to VND15.4 trillion ($670 million). The bourse saw 233 stocks gain and 201 lose.
The VN30 basket, which comprises the 30 largest capped stocks on the HoSE, saw 14 tickers in the green, led by TCB of the largest private lender Techcombank, up 3.1 percent, and MBB of Military Bank, up 2.6 percent.
The two lenders also saw the highest trading volume in the basket this session with 31.6 million MBB shares and 26.4 million TCB shares being traded.
Both tickers have been strong gainers this year, with the MBB share now at an all-time high of VND27,400, while TCB has climbed over 27 percent since the end of January when the market had plummeted.
Some other lenders in the green included STB of Ho Chi Minh City-based lender Sacombank, up 1.1 percent, and HDB of HDBank in the same city, up 0.6 percent.
Among the top five blue chip gainers, SBT of sugar producer Thanh Thanh Cong – Bien Hoa Jsc and SSI of SSI Securities Corporation were in third and fourth place respectively, both going up 2.3 percent.
The fifth place was taken by VJC of budget airline Vietjet, up 1.8 percent to VND134,000, its new peak this year.
Among the biggest losers were MSN of conglomerate Masan Group, down 2 percent, followed by PNJ of Phu Nhuan Jewelry, 1.9 percent, and FPT of IT giant FPT Corporation, down 1.7 percent.
Foreign investors were net sellers for the third session in a row to the tune of VND700 billion. Sales was dominated by several tickers including MBB, HSG of steelmaker Hoa Sen Group and CTG of state-owned lender VietinBank.
The HNX-Index for stocks on the Hanoi Stock Exchange, home to mid and small caps, gained 0.34 percent, while the UPCoM-Index for stocks on the Unlisted Public Companies Market fell 0.13 percent.