An exercising device includes a control handle having a limit flange, a retaining ring mounted on the limit flange, a mounting seat combined with the retaining ring to limit the limit flange between the mounting seat and the retaining ring, a driven member mounted on the mounting seat, a stop member mounted on the driven member, and a weight member located between the mounting seat and the stop member. Thus, the weight member is adjustably mounted on the driven member to adjust the relative position between the weight member and the mounting seat and to adjust the damping force applied by the weight member onto a user's hand. In addition, the stop member can stop movement of the weight member to prevent the weight member from being detached from the driven member due to an excessive centrifugal force.