The utility model relates to a soil sample grinder, comprising a support frame, wherein the top end of the support frame is connected with a movable bar in a hinged manner; the support frame at the lower part of the movable bar is fixedly connected with a cross bar of which the tail end is provided with a position limiting hole; one end of the movable bar is connected with a pull wire; the pull wire passes through the position limiting hole, and the bottom end of the pull wire is connected with a pressing block; the lower part of the pressing block is correspondingly provided with a base; and a ring-shaped soil storing groove is sleeved at the outer part of the base and is movably connected with the support frame. The soil sample grinder is simple in structure, is convenient to operate, can be conveniently used by a user to crush a large quantity of soil samples, satisfies the requirement of the user on conveniently grinding the large quantity of soil samples, and has higher practical value.