The woman was walking with a man in Thurnscoe, near Barnsley, last night when she was hit by an unknown vehicle.
She suffered serious injuries and was taken to hospital, where she died.
The vehicle did not stop at the scene, but officers have since made two arrests.
South Yorkshire Police today appealed for witnesses and anyone with information to come forward.
A spokesman said the woman was knocked down around 200 yards from the vehicle scrap yard on Barrowfield Road at around 7.30pm.
He said: “An investigation has been launched into the circumstances surrounding the collision and officers are keen to hear from any witnesses.
“A 36-year-old man and a 26-year-old woman have been arrested on suspicion of causing death by dangerous driving and are currently in police custody today.”
Contact 101 or email [email protected] and quote incident number 1110 of 24 October 2016.