A barbell is provided. The barbell includes a main body and two holding elements. The main body is elongated and hollow to enclose a receiving room. The receiving room is adapted for being filled with fluid or solid. The main body defines a longitudinal direction. The main body is formed with at least one positioning recess on the outer surface thereof. Each holding element is movable sleeved onto the main body. The holding element has a positioning element which is selectively abutted against the positioning recess to position the holding element on the main body. The holding element further has a holding portion for holding.