To provide a method for producing an endless sling formed from a wire rope, which is easily formed in a short time without requiring a complicated tool even in the case of a long inner perimeter or a large diameter.

The method for producing the endless sling includes a step of temporarily tacking an approximately central part of a wire rope not requiring untying to a temporary core rope retained tubularly at a connection part and extending a first twist part and a second twist part at both ends of the wire rope in both directions, a first twist step of helically twisting the wire rope while rotating the wire rope so as to wind the wire rope on the temporary core rope in the twist direction with one end around the temporary core rope, a second twisting step of helically twisting the wire rope while rotating the wire rope so as to wind the wire rope on the temporary core rope in the twist direction with the other end around the temporary core rope, and a step of crossing both ends and inserting the first twisted part and the second twisted part as rope cores instead of the temporary core rope while releasing the connection and extracting the temporary core rope.