Samantha Davis, 29, is thought to have left the Imperial Crescent area, in Town Moor, at around 2:30pm this afternoon, November 12.
Police are concerned for her wellbeing and need to ensure her safety.
They would like to hear from anyone who has seen or spoken to her today, or who knows where she might be.
Samantha is described as about 5ft 6ins tall and has shoulder length blonde hair with a green tinge and brown roots.
She is thought to be wearing a white knitted jumper, grey jogging bottoms and an orange parker coat.
Anyone with information as to her whereabouts should call South Yorkshire Police on 101 quoting incident number 535 of November 12.