To facilitate handling by making the weights of a dumbbell attachable and detachable to a bar-shaped body, to make the dumbbell effective for dumbbell exercises by variously changing the amounted weight of the weights, to facilitate the carriage of the dumbbell itself by eliminating the weight while avoiding the accident of drop in comparison with iron dumbbells, to handle the dumbbell easily for the child or the female, to improve decorativeness and to remarkably improve merchandise value.

A bar-shaped body 2, for which a handle part 1 is formed, is formed into a hollow body made of synthetic resin. One or plural weights 2 formed into hollow bodies made of synthetic resin are freely attachably and detachably provided at both the terminal parts of the bar-shaped body 2. Injection holes for replenishing weight members 4 such as water, sand or coins are formed respectively at the bar-shaped body 2 and the weights 3, and caps 6 for closing are freely attachably and detachably added to the injection holes.