A lens assembly according to an embodiment may include: a first pin; a first housing which moves along the first pin; a first lens group arranged in the first housing; and a first wheel which is arranged in the first housing and moves along the first pin. The first wheel may include a first rotation shaft coupled to the first housing, and a first rotation part which rotates about the first rotation shaft. The first rotation part may include a groove corresponding to the first pin, wherein the maximum depth of the groove may be less than one-half the maximum thickness of the first pin in a direction perpendicular to the first rotation shaft.