Michael Gove and his wife Sarah left their young son at a bed and breakfast while they partied with celebrities, it hasd been reported.
The 11-year-old is said to have wanted to stay in and watch TV rather than go to the function where his father was spotted on the dance floor.
Government guidelines say that children under 12 should not be left alone for a long period of time and if they are harmed in their absence parents can be prosecuted.
However, the "mature" boy was left under staff supervision.
Mr Gove, former education secretary and chief whip, launched a failed bid to lead the Tory party in the wake of the EU referendum, in which he betrayed his ally Boris Johnson. After keeping a low profile since the debacle, the 48-year-old went out with his journalist wife Sarah Vine to attend a party celebrating the end of the Cheltenham Literature Festival.
According to the Sunday Mirror, they left the youngster with staff at the £250-a-night guesthouse, returning at 1.30am the following morning.
Later, comedian Dom Joly tweeted: "Amazing party at @131TheProm celebrating end of Chelt Lit Fest- only slightly ruined by the sight of the loathsome Michael Gove dancing..."
A spokesman for the family told the Sunday Mirror: "Michael and Sarah's son is a mature and confident secondary school pupil. He preferred to watch TV rather than go out to dinner.
"He was perfectly fine and staff at the 13-room hotel were happy to supervise.
"The hotel where Michael, Sarah and their son were staying would know how to get in touch with them if anything distressing had occurred."