A juicer having improved juicing performance, including: a housing in which a motor is built in; a screw housing detachably coupled to the housing; and a driving screw exposed to one side of the housing and received in the screw housing so as to rotate by being coupled to a driving shaft rotatably driven by the motor. The driving screw includes: a driving screw main body in which an installation groove opened toward the housing is formed; one or more piezoelectric element provided in the installation groove of the driving screw main body; and a contact terminal electrically connected to the piezoelectric element and electrically contacting a contact electrode provided in the housing.