The utility model discloses a rail web rust removal grinding machine. The rail web rust removal grinding machine comprises a first grinding wheel used for grinding the left side face of a rail web of a steel rail, a second grinding wheel used for grinding the right side face of the rail web of the steel rail and a main machine frame. A tail machine frame is arranged at one end of the main machine frame and a first fixing frame and a second fixing frame are arranged at the other end of the main machine frame. A first work head used for driving the first grinding wheel to rotate is installed on the first fixing frame. A second work head used for driving the second grinding wheel to rotate is installed on the second fixing frame. The left side and the right side of the tail machine frame are respectively provided with walking wheels walking along the lower bottom face of a rail jaw of the steel rail. The tail machine frame is provided with two first guide wheels walking along the left side face of the rail jaw of the steel rail and along the right side face of the rail jaw of the steel rail respectively. The end, far away from the tail machine frame, of the main machine frame is provided with two second guide wheels walking along the left side face of the rail jaw and along the right side face of the rail jaw respectively. The rail web rust removal grinding machine is stable in operation, good in grinding effect, simple in structure and convenient to disassemble, assemble, popularize and use.