PROBLEM TO BE SOLVED: To improve the longitudinal center of gravity balance of a riding rice transplanter and to improve a steering property by arranging a transmission case at the lower position of an engine to be at least partially overlapped with the engine, and locating the rear end of the transmission case near directly below the rear end of a hood. SOLUTION: In a riding rice transplanter A connected with a planting section C to the rear via a lift mechanism D, an engine 2 is mounted on the front upper sections of upper frames 1, 1 arranged on both sides of a substrate to form a travel section B. A transmission case 5 is arranged at the lower position of an engine 2 to be at least partially overlapped with the engine 2 in the vertical direction. The transmission case 5 is arranged protrusively below the upper frames 1, 1, and the rear end of the transmission case 5 is located at the position near directly below the rear end of a hood 4. Front axle cases 6 are interlockingly arranged on both the right and left sides of the rear section of the transmission case 5 to connect the right and left front wheels 7-1.
