The invention discloses a device for breaking walnut shells and taking walnut kernels, having functions of self-positioning, pre-breaking shells, equidirectional spiral self-grading and flexible extrusion. The device comprises an intermittent feeding device, the a shell pre-breaking device, a flexible shell breaking device and a separating device, which are fixed on a machine frame, wherein the intermittent feeding device is used for performing intermittent batch feeding for the shell pre-breaking device; the shell pre-breaking device comprises an extruding part and a blanking part which are mutually matched; the extruding part is in reciprocating movement, and is matched with the blanking part for extruding walnuts, so that cracks are generated in the walnuts; the blanking part is in reciprocating movement, so that the extruded walnuts fall off to the flexible shell breaking device; the flexible shell breaking device is used for breaking walnut shells; and shells and kernels of the walnuts after shell breaking are separated for storage through the separating device. The device disclosed by the invention integrates a plurality of systems, and is compact in structure, the manufacturing cost of a machine is reduced, the occupied space for the operation of the machine is also reduced, and the miniaturization and the high efficiency of the machine are facilitated; in structure design, multiple connections including splicing, combining and the like for cooperating work can be realized; and the requirements of various production scales and the requirements of various production sites can be met, and the device is also suitable for families, and is widely applied.