"Patient 335," 24, from the northern province of Thai Nguyen, has been living and working in the Middle Eastern country for two years.
He returned to Vietnam on repatriation flight QH9092 of Bamboo Airways that landed in Ho Chi Minh City Tuesday before being sent to a quarantine camp.
After testing Covid-19 positive, he has been transferred to the HCMC Hospital for Tropical Diseases for treatment.
Of Vietnam's total Covid-19 tally of 335, 195 are overseas returnees, all quarantined upon arrival.
Vietnam has organized several special flights in the last few months to repatriate thousands of citizens wanting to return home to avoid facing the Covid-19 pandemic elsewhere.
On Monday and Tuesday, 678 Vietnamese were brought home on three flights from Canada, Africa and the Middle East. Passengers paid their own fares.
Saturday morning marks day 62 that Vietnam has gone without community transmission of the novel coronavirus.
The Covid-19 pandemic has affected 213 countries and territories, with more than 445,000 deaths reported.