PURPOSE: To surely activate a jumping force irrespective of a landing spot by adjusting the buoyancy of a balloon not to exceed the weight of one's body and connecting the balloon having the buoyancy to the body.

CONSTITUTION: A balloon 1 filled with helium gas is enclosed and a balloon reinforcing rope 2 is trained around the balloon 1. Tough rubber ropes 3, 3 are connected to one ends of the balloon reinforcing rope 2 and provided on the lower ends with a belt 4 connected to one's body to constitute a jumping implement. To balance the weight of the body with the buoyancy of the balloon 1, a weight 7 is adjustably mounted to the balloon 1. The belt 4 of the jumping implement 5 is surely mounted to a user for the completion of preparation. Since the buoyancy not exceeding the weight is always transmitted to the body, a jumping force can surely be provided irrespective of a landing spot. Since the landing spot is not cared, a view can be enjoyed during the jumping and, since the landing spot is not restricted, the jumper can freely move.