The cases in HCMC include 232 in quarantined zones and isolated areas, while 38 other cases have unknown sources of transmission.
The remaining six cases were detected in four other localities.
The central Phu Yen Province got two cases that are people who had made contact with confirmed Covid-19 patients.
Dong Nai Province that borders HCMC reported two cases, with one returning from HCMC and the other being contact traced.
The case in Ba Ria-Vung Tau Province, another HCMC's neighbor, is a man from the central Ha Tinh Province who has come into contact with an existing case.
The case in the central Ha Tinh Province is a 11-year-old boy who had contact with a Covid-19 patient.
Since the new wave started on April 27, 18,838 local cases have been recorded in 55 cities and provinces, with HCMC accounting for the most infections, at 7,655.
Vietnam has vaccinated more than 3.92 million against the new coronavirus and 235,570 of them have got two doses.