The landing ship docked in Ho Chi Minh City, the epicenter of Vietnam's latest wave, on Monday, an Indian government statement said.
"The ship is carrying 100 metric tons of liquid medical oxygen in five containers and 300 oxygen concentrators of 10 LPM (liters per minute) capacity each based on the requirement projected by the government of Vietnam."
The Airavat, from the Eastern Naval Command based at Visakhapatnam, is on a deployment to Southeast Asia for shipment of Covid-19 relief aid.
It docked in Jakarta, Indonesia, on August 24 to deliver 10 liquid medical oxygen containers.
"India and Vietnam enjoy a strong traditional bond of friendship," the statement said.
"Symbolizing our commitment to the comprehensive strategic partnership with Vietnam," INS Airavat arrives in HCMC with relief aid to strengthen Vietnam's efforts against Covid-19, the Indian Ministry of Petroleum and Natural Gas tweeted.
The ship has since left to deliver more medical supplies to other nations in the region.
In June it had transported medical supplies including liquid oxygen tanks and ventilators from Vietnam and Singapore to India to tide over a temporary shortage.
Vietnam was hit by a fourth wave of Covid four months ago and has yet to bring it under control.
By Monday the number of infections had climbed to 445,292, with more than 11,000 fatalities.