Heidi is a book of children's fiction published in 1881 by Swiss writer Johanna Spyri.

It was initially published in two sections Heidi: Her years of wandering and learning and Heidi: How She Used What She Learned.

It is a book about the incidents of the life of a 5-year-old girl in her concerned grandfather's care in the Swiss Alps, which describes the story of a little orphan girl, Heidi, who has been sent to stay with a lonely, irritating man at the highest point of a mountain in the Swiss Alps.

This man is her grandfather. Heidi had been previously living with her Auntie Dete, but now Dete has been selected for a job in Frankfurt.

The story also has five series that show Heidi as a grown-up, a mother, and, afterward, a grandmother, despite the fact that they were written after Spyri's death and involve her writings as inspiration.