A Sydney father who allegedly fractured his son’s skull during a fight has been charged with grievous bodily harm.

The son, 25, was taken to Nepean Hospital after Friday night’s alleged assault, police said.

Soon after the attack at Cambridge Park, in Sydney’s west, the 48-year-old man was charged with causing grievous bodily harm to a person with intent.

He was refused police bail and is due before Parramatta Bail Court on Saturday.

A crime scene has been established and investigations continue.