An Old-Fashioned Girl is a novel by Louisa May Alcott.

It was first serialised in the Merry's Museum magazine between July and August in 1869 and consisted of only six chapters. For the finished product, however, Alcott continued the story from the chapter "Six Years Afterwards" and so it ended up with nineteen chapters in all. The book turns around Polly Milton, the old-fashioned girl who titles the story. Polly visits her wealthy friend Fanny Shaw in the city and is overwhelmed by the fashionable and urban life they live––but also left out because of her "countrified" manners and outdated clothes.