Teresa Vickers was last seen around 9.10pm walking towards Edwinstowe at the junction of the A616 and A6075.
The 48-year-old, who has links to the Rotherham and Harworth areas, is white, of thin build and has black hair in a bob.
She was wearing grey jogging bottoms, a cream t-shirt, a beige striped jumper and black shoes when she was last seen.
A spokesman for Nottinghamshire police said that Teresa may be in an agitated state and in need of urgent medical attention due to the length of her absence.
Police are urging anybody with information to call 101 and quote incident number 835 of 31 July 2015..