Heidi is a Swiss work of fiction, originally published in two parts as "Heidi's years of learning and travel" and "Heidi makes use of what she has learned". It is a novel about the events in the life of a young girl in her grandfather's care in the Swiss Alps. The book was written "for children and those who love children" (as quoted from its subtitle) in 1880 by Swiss author Johanna Spyri.

Heidi is one of the best-selling books ever written and is among the best-known works of Swiss literature.

Dozens film or television productions based on the original story have been made. The Heidi movies were popular far and wide, becoming a huge hit in several countries around the world. Shirley Temple starred in the 1937 motion picture in the title role.