Seed drying machine

The utility model relates to the technical field of drying machines, and discloses a seed drying machine which comprises a drying box, a first rotating seat is fixed to the right end of the top of the drying box, a second rotating seat is fixed to the left end of the top of the drying box, and a crank is rotationally connected to one side of the first rotating seat. According to the seed drying machine, a second screen is driven to move by rotating a first threaded rod, so that a filtering hole between the first screen and the second screen is adjusted, seeds are screened through cooperation of a first rotating seat, a second rotating seat, a crank, a connecting rod and a driving motor, and the seeds penetrate through the filtering hole to enter the drying box to be dried; and impurities such as straw and gravel slide down from the top of the first screen and are collected by a worker, so that the situation that the impurities such as straw and gravel are possibly doped in the seeds is avoided to a certain ex