PROBLEM TO BE SOLVED: To provide a combine harvester which can store a sufficient amount of grains in a grain tank, even when a sensor for detecting the amount of the grains is disposed in the grain tank.SOLUTION: A charging port sensor 300 is positioned on a non-guiding surface 141b side facing the guide surface 141a of a casing 140. Thus, grains collide with the charging port sensor 300 in a smaller amount than that on the side of the guide surface 141a, and the grains are uniformly accumulated in the grain tank 4. The charging port sensor 300 is positioned on the side of a ceiling surface rather than the charging port 4b. Therefore, it is prevented that the charging port sensor 300 is buried in the grains, before the grain tank 4 is filled. Since the amount of grains colliding with the charging port sensor 300 is small, the abrasion amount of the charging port sensor 300 can be reduced, and the sensing volume of the charging port sensor 300 can also be reduced.
