A juice extractor capable of extracting juice from vegetables, fruits or soymilk from beans is disclosed. The extractor includes a housing having a draff outlet port and a juice outlet port, a screw having an upper rotary shaft inserted in a rotary shaft hole of the housing and a lower rotary shaft with a plurality of screw spirals formed on an outer periphery thereof, and a mesh drum for extracting the juice toward the juice outlet port, and a rotary brush mounted between the housing and the mesh drum and having a brush holder. Various nutrients and intrinsic flavor contained in the vegetables or fruits are maintained to the fullest extent by employing a very low speed screw of a squeezing mode. Also, since the housing accommodating the screw is vertically fixed to an upper portion of a drive unit, the material is automatically moved downward without pressing the material down, and the draff is discharged while squeezing and grinding the materials put in an inlet port.