A juice extractor comprising a juice extracting drum accommodating inside a screw compressing a material for juice extraction; a cylindrical hopper coupled to an upper portion of the juice extracting drum and having a space for accommodating the material for juice extraction; and a cutting part capable of rotating inside the hopper and cutting the material for juice extraction put inside the hopper; wherein at the center of the bottom surface of the hopper, a connecting hole is formed which connects the screw and the cutting part such that power can be delivered, and the cutting part is rotatably coupled with the screw through the connecting hole, to rotate by receiving a rotation force of the screw located inside the juice extracting drum, the cutting part is supported only at the lower end of the hopper such that inside the hopper an open space for putting in the material for juice extraction is formed above the cutting part including its center of rotation; through an outlet formed on the bottom surface of the hopper, the cut material for juice extraction is supplied inside the juice extracting drum located below the hopper; the cutting part comprises a chopping blade extending upward in a hook form from the center of rotation of the cutting part which rotates and is supported only at the lower end of the hopper and having an upper end with a cross-section that becomes smaller as it gets closer to the end; and a slicing blade, shredding the material for juice extraction that has moved downwards after being shredded by the chopping blade, extending horizontally on a lower end surface of the hopper from the center of rotation of the cutting part and having a predetermined thickness in a vertical direction for pushing the material for juice extraction placed on the bottom surface of the hopper; the height of an upper end of the chopping blade is formed to be at least higher than the height of an upper end surface of the slicing blade; and a first inner protrusion is formed that protrudes inwardly from an inner surface of the hopper to support the material for juice extraction so as to interact with the chopping blade when the cutting part rotates. a juice extracting drum accommodating inside a screw compressing a material for juice extraction; a cylindrical hopper coupled to an upper portion of the juice extracting drum and having a space for accommodating the material for juice extraction; and a cutting part capable of rotating inside the hopper and cutting the material for juice extraction put inside the hopper; wherein at the center of the bottom surface of the hopper, a connecting hole is formed which connects the screw and the cutting part such that power can be delivered, and the cutting part is rotatably coupled with the screw through the connecting hole, to rotate by receiving a rotation force of the screw located inside the juice extracting drum, the cutting part is supported only at the lower end of the hopper such that inside the hopper an open space for putting in the material for juice extraction is formed above the cutting part including its center of rotation; through an outlet formed on the bottom surface of the hopper, the cut material for juice extraction is supplied inside the juice extracting drum located below the hopper; the cutting part comprises a chopping blade extending upward in a hook form from the center of rotation of the cutting part which rotates and is supported only at the lower end of the hopper and having an upper end with a cross-section that becomes smaller as it gets closer to the end; and a slicing blade, shredding the material for juice extraction that has moved downwards after being shredded by the chopping blade, extending horizontally on a lower end surface of the hopper from the center of rotation of the cutting part and having a predetermined thickness in a vertical direction for pushing the material for juice extraction placed on the bottom surface of the hopper; the height of an upper end of the chopping blade is formed to be at least higher than the height of an upper end surface of the slicing blade; and a first inner protrusion is formed that protrudes inwardly from an inner surface of the hopper to support the material for juice extraction so as to interact with the chopping blade when the cutting part rotates.