<;P>;PROBLEM TO BE SOLVED: To provide a three-wheeled traveling device movable not only in the longitudinal direction but also in the lateral direction. <;P>;SOLUTION: This three-wheeled traveling device has a first wheel 110 and a second wheel 120 having a wheel shaft arranged on the same straight line, a third wheel 130 arranged between the first wheel and the second wheel and having a wheel shaft arranged on a horizontal straight line orthogonal to an extension line of the wheel shaft of the first wheel and the second wheel, driving means arranged in the respective wheels so as to separately drive the first wheel, the second wheel and the third wheel, and a control means for controlling the respective driving means. The respective wheels 110-130 have a plurality of rotary bodies 31 juxtaposed along outer peripheries of the wheels. <;P>;COPYRIGHT: (C)2009,JPO&INPIT