The index closed 2.1 points up after gaining 4.01 points Monday.
Trading on the Ho Chi Minh Stock Exchange rose marginally to VND15.97 trillion ($682.8 million), marking the ninth straight session above the VND15-trillion threshold.
The VN-30 basket, comprising the 30 largest capped stocks, saw 16 tickers gain.
HPG of steelmaker Hoa Phat rose 2.1% to a two-month high.
NVL of property developer Novaland gained 1.8% to the highest since April 14. It have risen 13% in nine recent sessions.
Other gainers were VIC of Vietnam's biggest conglomerate Vingroup, up 1.1% and VJC of budget carrier Vietjet, up 1%.
Thirteen tickers fell, led by VCB of Vietcombank with a 1.5% loss.
It was followed by VHM of property developer Vinhomes, down 1%, and PLX of fuel distributor Petrolimex, down 0.8%.
Foreign investors net sold for the third straight session to the tune of VND70.27 billion. They mainly sold HPG, VNM of diary giant Vinamilk, and VHM.
The HNX-Index at the Hanoi Stock Exchange, where mid and small caps list, increased 0.03% while the UPCoM-Index at the Unlisted Public Companies Market was up by 0.58%.