Two women have been charged over an alleged break and enter at Claymore in Sydney's south-west overnight that ended in a fatal brawl.

Macquarie Fields police were called to a home on Leigh Street about 9:00pm last night, after receiving reports a number of people were fighting.

Police spokeswoman Joanne Elliott said when officers arrived they found a 33-year-old man unconscious.

He was taken to Campbelltown Hospital where he later died.

"A crime scene has been established and the exact circumstances of how this man has died and what's led up to it are still being investigated," Ms Elliott said.

Two women, aged 32 and 33, were arrested at the scene and later charged with aggravated break and enter.

Police said they believed the man who died was not a resident of the Claymore house, but broke into the home with the two women.

The women were refused bail and are expected to appear at Campbelltown Local Court later today.

A 34-year-old man was also arrested at the scene and taken to hospital for treatment under police guard, but has since been released pending further inquiries.

Ms Elliott said police were continuing to investigate the incident, and were being assisted by officers from the State Crime Command's Homicide Squad.