The invention mainly relates to seed melon pulp excavating machine equipment, in particular to a pulp excavating knife structure for a seed melon pulp excavating machine. A pulp excavating knife for a seed melon pulp excavating machine comprises a pulp excavating knife rest, knife edges, a knife handle and bolts for fixing the knife edges, and is characterized in that: the pulp excavating knife rest is an assembly welding piece; and five knife edge fixing seats with the inclinations of 9 degrees, 12 degrees, 15 degrees, 15 degrees and 12 degrees are welded on the bottom surface of square steel and are used for clamping the knife edges. Each knife edge is connected with a fixing seat through two M6 countersunk head bolts; a sleeve is connected with the knife handle of the pulp excavating knife through an M10 pin; the knife handle is made of a cold-drawing seamless pipe and is connected with a motor II through a sleeve coupler; and the knife edges are made of stainless steel, forged into gradually distorted knife edges at equal angles, the front knife surfaces are gradually reduced, and the whole outlines of the knife edges are in spherical bent shape. The invention has the advantages that: the pulp excavating knife is simple in structure and works reliably; the excavating rate is improved by optimizing the shapes of the knife edges; the fineness of the pulp is ensured through multi-edge excavating; and a foundation is laid for subsequent processing of seed melons.