A shear bonding device and a shear bonding method of metal plates are disclosed. The shear bonding device may include: an upper shear bonding mold having more than one upper perpendicular tooth and more than one upper slanted tooth formed alternately on a front end surface thereof; a lower shear bonding mold overlapped with the upper shear bonding mold in a vertical direction by a predetermined width below the upper shear bonding mold, and having more than one lower perpendicular tooth corresponding to the more than one upper slanted tooth and the more than one upper perpendicular tooth corresponding to the more than one lower slanted tooth formed alternately on a front end surface confronting the upper shear bonding mold; an upper heating clamper including a front end surface contacting with the upper perpendicular tooth of the upper shear bonding mold and adapted to generate heat by receiving power from a power supply; a lower heating clamper including a front end surface contacting with the lower perpendicular tooth of the lower shear bonding mold and adapted to generate heat by receiving power from the power supply; upper and lower pressing cylinders moving the upper and lower shear bonding molds upwardly or downwardly so as to apply load; and upper and lower clamping cylinders moving the upper and lower heating clampers upwardly or downwardly so as to apply clamping force and load, wherein the metal plates are disposed between the upper shear bonding mold and heating clamper, and the lower shear bonding mold and heating clamper.