The investigation follows reports that a Buckingham Palace staff member was arrested after a Christmas party, a palace spokesman said.
A spokesman said “appropriate measures” would be taken after the palace was informed of the incident.
The Sun reported that a member of staff was arrested at a bar in Victoria on Tuesday.
A palace spokesman told the BBC: “We are aware of an off-site incident involving a number of household staff who had previously attended an early evening reception at the palace.
“Although this was an informal social gathering, not an official Christmas party at the palace, the facts will be fully investigated, with a strong disciplinary process in relation to individual staff members and appropriate action taken.
The Metropolitan Police told The Sun officers were called to the Victoria Street bar after a customer “smashed glasses and attempted to assault a member of staff”.
They said a 24-year-old woman was arrested on suspicion of common assault, criminal damage and being drunk and disorderly before being released after paying a fine.
The Metropolitan Police was contacted for comment.