Disclosed herein is a footwear sole. The footwear sole includes a coupling seat (120), a connector (230) and a locking pin. The coupling seat protrudes from the lower surface of a rear midsole(100b), and includes a through hole (121) in a central portion thereof, a locking recess (122) formed around the through hole, and at least four pin slits (123) formed at regular intervals. The connector is coupled to the top of the coil spring, and includes a locking protrusion (231) corresponding to the locking recess, an internal threaded part, and a spring seat (233) provided along an edge of an upper surface of the connector. The locking pin is provided at an end of the top of the spring, and protrudes to be fitted into an associated pin slit.
