A 20-year-old man has been knocked unconscious after being punched in the head during a street fight in Lawnton, about 11 kilometres from North Lakes.

He was taken to the Royal Brisbane Hospital in a serious condition with head injuries.

Police were called to the intersection of Rose and Tulip streets just after midnight on Saturday over two men fighting while a party was being held nearby on Tulip Street.

A crowd of people were dispersed from the scene when police officers arrived.

No arrests have been made but police endeavour to speak with the injured man.