The 18-year-old man who kicked a security guard in the head at a music festival has been sentenced to eight months jail and banned from attending festivals for two years.

Martin Fulton in June pleaded guilty in Perth Magistrates Court to assault, occasioning bodily harm, and trespassing after he jumped the fence at the Good Life Festival on February 27 and kicked security guard Michael Rigby in the head as he was trying to restrain another man.

The incident was caught on video and went viral shortly after the festival.

During his sentencing on Tuesday, Chief Magistrate Stephen Heath described the attack as "random and cowardly".