Linear vibrating sieve uses double vibrating motors to drive,when two motors rotate synchronously and reversely, exciting forces generated by eccentric block are resolved in parallel to the direction of motor axes and then united as one across the motor axis direction, so its movement track is linear. There is an angle of inclination between the two motor axis relative to the screen deck. Under the influence of the resultant force of exciting force and materials itself weight, materials are thrown up to make leapfrog and linear movement forward on the screen deck in order to screen and grade the material. Applied in flowing line to achieve automatic operation.