A 95-year-old woman who was hospitalised after being tasered at a nursing home has died, with a police officer facing three criminal charges over the incident.

Clare Nowland was using a walking frame when she was allegedly tasered by Senior Constable Kristian White last week at Yallambee Lodge aged care facility in Cooma, NSW, after failing to drop a steak knife.

Ms Nowland, who had dementia and weighed just 43kg, sustained critical injuries, including a fractured skull.

She died in hospital on Wednesday night.