PROBLEM TO BE SOLVED: To make rear wheels of rice transplanter into crawlers without causing inconvenience in which pushing in mud damages the surface of a paddy field to exert a bad influence on a planting state, a crawler drag in rotation is severe to damage a butt, the center of rotation is changed when an undulation or unevenness exists on the ground to make an operation difficult. SOLUTION: Crawler traveling apparatuses of triangular stretch structure each obtained by a winding crawler belt 13 on a front and a rear driven wheels 10 and 11 and a driving sprocket 12 are arranged at the right and left parts of the rear parts of a main body, respectively. A pair of a right and a left operating wheels 1 are installed ahead the crawler traveling apparatuses 2. Grounding length Lr in the longitudinal direction of the crawler traveling apparatuses 2 is set 1.2-1.5 diameter Df of the operating wheels 1. A shaking angleαof front rising around a support P of the crawler traveling apparatus 2 is set larger than a shaking angleβof rear rising.
