Police are trying to find the ex-partner of a woman found dead in her home near Nelson.

The 39-year-old woman was found at her home in Salisbury Road, Richmond, about 14km south of Nelson, about 6.30pm on Thursday.

Detective Inspector Geoff Jago says she had died from an assault, though he wouldn't say what her injuries were or if any weapons had been used.

"The family of the victim have indicated that she has recently ended a relationship," he told media on Friday.

"Locating that person is one aspect of the investigation."

He said it wasn't known if the ex-partner was still in the Nelson-Richmond area.

The woman had been in contact early on Thursday morning but family and work colleagues became concerned later in the day when she didn't turn up for work.

Det Insp Jago said police wanted to hear from anyone who might have seen something suspicious in Salisbury Road, one of Richmond's main roads.

He said there was no sign of a break-in.

About 20 detectives and a number of forensic scientists are involved in the homicide investigation.