A bumper device of a robot cleaner, and a robot cleaner equipped with the bumper device are disclosed. The bumper device of a robot cleaner includes: a bumper housing coupled to cover an outer circumferential surface of a main body of a robot cleaner, made of a material for restraining an expansion, and having an internal passage; an air tube insertedly installed inside the bumper housing so as to be expandable along the internal passage; and a sensing unit for sensing expansion of the air tube. Even if an impact is applied to any position of front, side and rear surfaces of the main body, it can be lessened in its transfer to the robot cleaner.