A mother of four has been stabbed to death by her abusive partner soon after the pair left a court dispute in Melbourne's west, police say.

Homicide detectives have confirmed there was a restraining order out against the killer, and that he had a history of domestic abuse against the woman.

Police inspect the Sunshine shopping area where a mother of four was stabbed to death. Credit:Jason South

The Melton West woman, 33, had been at Sunshine Magistrates Court on Wednesday because of a dispute with her de-facto husband of 18 years. She then went to a nearby women's refuge and to her solicitor's office on Hampshire Road, Sunshine.

Three minutes after walking out the door, her de-facto husband, 38, of Sunshine North, stabbed her multiple times in the chest with a fishing knife, according to police.