PROBLEM TO BE SOLVED: To provide a paddy field working machine easily preventing a fuel tank from grounding on and entering mud, while avoiding and suppressing a decrease in a capacity of the fuel tank.SOLUTION: The paddy field working machine includes: side steps 35 provided at lateral sides of a driver seat 30 and a working step 41 disposed at a car body rearward side of the side steps 35 in height higher than the side steps 35 and rear wheels 3. A fuel tank 50 for an engine is disposed at a lower part of the working step 41 and a car-body lateral outward of a car body main frame 20 that is placed in a car body longitudinal direction. The upper ends of the tank body 51 and a fuel supply part 52 of the fuel tank 50 are located at positions higher than that of the side steps 35.
