Sophie, Countess of Ségur (née Countess Sofiya Feodorovna Rostopchina; Saint Petersburg, 1 August 1799 - Paris, 9 February 1874) was a French writer of Russian birth.

She is best known today for her novel Les Malheurs de Sophie (Sophie's Misfortunes). The action takes place in a castle in the French countryside during the Second French Empire, where Sophie lives with her parents Mr and Mrs de Réan. Curious and adventurous, she does one silly thing after another, with the critical help of her cousin Paul, who is good and tries to show her the right path. She has two friends, Camille and Madeleine de Fleurville, 'good little girls' whom she tries hard to imitate. But she will learn that life is not a bed of roses...

It was in her father's salon that Sophie Rostopchine met Eugène Henri Raymond, Count of Ségur, whom she married on 13/14 July 1819. The marriage was largely an unhappy one: her husband was flighty, distant and poor (until being made a Peer of France in 1830), and his infrequent conjugal visits to their château des Nouettes produced eight children, including the father of the historian Pierre de Ségur (Eugène de Ségur is said to have called his wife "la mère Gigogne", or "Mother Gigogne" in reference to a theatre character of 1602, an enormous woman out of whose skirts a crowd of children appeared).

The Comtesse de Ségur wrote her first novel at the age of 58.