The new cases are a 44-year-old woman in Da Nang and a 33-year-old man in Hai Duong city, eponymous northern province.
Since July 25, 534 cases of infection linked to Da Nang have been identified.
More than 77,000 people are in quarantine, including 2,095 in hospitals, 19,808 in places of containment and 50,477 at home.
On Sunday August 23, five COVID-19 patients were announced cured, bringing the number of recoveries in Vietnam to 568.
The country has so far deplored 27 deaths.
Of the patients undergoing treatment, 39 tested negative for the virus once, 49 more twice and 28 three times. -VNA