A woman has died after she was allegedly attacked by her partner at a home in Sydney's west.

Police allege the man, 46, assaulted the woman, 51, after they had an argument at their Quakers Hill home on Monday morning.

Paramedics found the victim with head trauma, serious facial bruising and a collapsed lung at the Hillcrest Road property after being called to the scene about 6:00am.

She was taken to Westmead Hospital in a critical condition, and hospital staff contacted police.

The man appeared in court yesterday after being charged with assault occasioning grievous harm.

Police said further charges were likely.