The invention relates to the technical field of wire drawing dies, in particular to a diamond wire-drawing die. According to the diamond wire-drawing die, metal wires with various shapes can be drawn, adaptive capacity is improved, use limitation is reduced, the die can help a circular steel sleeve to resist extrusion force applied by a wire drawing device, and the circular steel sleeve is relatively protected and used for a long time. The wire-drawing die comprises a die core, the circular steel sleeve, two groups of fixing blocks, two groups of connecting blocks, two groups of first fixing springs, two groups of second fixing springs, two groups of pushing blocks, two groups of buffer spring sets and two groups of semicircular buffer plates, an inner hole of the die core is provided with a horn mouth, an inlet cone, a deformation cone, a calibrating strap and an outlet angle, fixing grooves are formed in the front half area and the rear half area of the left end of the die core, the fixing blocks are arranged in the fixing grooves, second slots are formed in the left ends of two groups of inserting blocks, the right ends of the pushing blocks are inserted into the second slots, and the semicircular buffer plates are arranged at the output ends of the buffer spring sets.