Stamp collecting is the collecting of postage stamps and related objects. It is an area of philately, which is the study of stamps. It has been one of the world's most popular hobbies since the late nineteenth century with the rapid growth of the postal service, as a stream of new stamps was produced by countries that sought to advertise their distinctiveness through their stamps.

The hobby of collecting includes seeking, locating, acquiring, organizing, cataloging, displaying, storing, and maintaining items that are of interest to an individual collector. Collections differ in a wide variety of respects, most obviously in the nature and scope of the objects contained, but also in purpose, presentation, and so forth. The range of possible subjects for a collection is practically unlimited, and collectors have realised a vast number of these possibilities in practice, although some are much more popular than others.