Hongkong Post said the two postmen’s daily duties involved back-office work and accepting mail items at counters behind a partition.
It added that the office will resume services after Wednesday, while the Post Office Box Lobby will remain open and the counters for mail collection will be reopened at 1pm Tuesday.
Members of the public have been advised to use the Sheung Wan Post Office or Wyndham Street Pot Office nearby.
Meanwhile, the Food and Environmental Hygiene Department (FEHD) also announced that one of its staff members has tested preliminary positive.
The department said the employee works at its office in the Fa Yuen Street Municipal Services Building in Mong Kok and last performed duties on February 21.
Its Food Import and Export Section there was shut on Tuesday for disinfection, with limited services expected for Wednesday.
The FEHD advised importers to head to its office on the eighth floor of the same building for consignment clearances.