Mainland China reported 18 new cases of COVID-19 on June 28, compared with 21 a day earlier, the national health authority said.
All of the new infections were imported cases, the National Health Commission said in a statement on Tuesday.
There were no new deaths.
The number of new asymptomatic cases, which China does not classify as confirmed cases, stood at 30, up from 22 a day earlier.
As of June 28, China had a total of 91,771 confirmed coronavirus cases, it said.
The death toll from the coronavirus remained unchanged at 4,636.