The Shrinking of Treehorn is a children's book by Florence Parry Heide, illustrated by Edward Gorey, and first published in 1971.

The main character in the book is Treehorn, whose parents barely notice when he shrinks.

The book opens with the line "Something very strange was happening to Treehorn," and the boy soon discovers that he is getting smaller when he cannot reach the candy bars and bubble gum he has hidden on a previously accessible shelf.

[2] In June 2019, an animated film adaptation directed by Ron Howard was said to be in development.

[4] However, on May 16, 2022, it was announced that the film had been acquired by Netflix with Howard's Imagine Entertainment as its production studio.