St Mirren have contacted police after a member of the public entered the stadium and ran on to the pitch.
The Scottish Premiership club say they have CCTV footage of the incident.
The Paisley side have also reminded fans to follow official government advice and stay at home during the coronavirus crisis.
"The individual involved has not followed government guidelines and could have caused himself serious injury," said St Mirren statement.
"We would like to make supporters aware of the dangers of entering the stadium illegally. Climbing the fence at the stadium could cause serious injury due to its height and the anti-climb spikes at the top.
"This type of situation will not be tolerated and CCTV footage has been passed on to the police."