Double roll crusher consists of roll wheel, roll bearing, pressing device, adjusting device and driving device etc.Discharging size adjustment: between two roller equipped with cuneate or gasket adjusting device, top of the wedge device capped with adjustment bolts. When the adjustment bolts pull upward wedge which will bear against the fixed wheel to make it deviate from the movable roller wheel, then the gap between wheels become large, discharging size become bigger, otherwise the opposite, gasket device is through the quantity or thickness to adjust the materials size. When adding gaskets the gap between wheels become large, when reducing gaskets the gap between wheels become small, so the discharging size becomes small. Driving structure is two motors through triangle belt drive to grooved pulley which drag roller rotating according to relative direction. In crushing stage, material is broken by roll wheel; final product is discharged from chassis. For safety, transmission part