Sergei Pronin had only just started work as an administrator at the Pushkin Gallery when the lockdown was imposed.
Granted permission to stay
He was granted permission to stay and now paints, sleeps, cooks and exercises in the company of a sole companion - a canary named Hertz.
Devoting time to art
He has finished painting a view of the gallery and is now working on a piece dedicated to poet Alexander Pushkin, after whom the gallery is named and whose sculpture features as a centrepiece of its main exhibition.
Planned to stay there
Pronin, who does daily aerobics and stretching in one of the gallery's several rooms, said he planned to stay there for the duration of the lockdown, which is currently in place in Russia until April 30.
The domed gallery, which opened in 1902, operated as a military hospital for a brief period during World War Two and now houses paintings by local artists and has a stage for concerts and theatre performances.
Museums and galleries have been among the many venues and businesses to close in an effort to contain the coronavirus, with 47,121 cases and 405 deaths reported in the country.