To provide a bookmark wherein a part of the bookmark is attached to a book to prevent its falling, and a retaining part for preventing tearing caused by free opening of the book and the bookmark are integrated.

An adhesive part 1, a bookmark part 4, and a part becoming a retaining part 2 are arranged in a board or a material having similar performance, and a retaining tool 3 is fixed to the retaining part 2. The adhesive part 1 is attached to the front cover or the back cover of a book, the bookmark part 4 is folded to be used as a bookmark, and the retaining part 2 is used for fixing by the retaining tool 3 to the back cover or the front cover during housing of the book or the like.