PROBLEM TO BE SOLVED: To provide a locking pin for scallop aquaculture in which the insertion of the locking pin containing a locking piece to a locking hole is easy and smooth, and the ear-hanging locking of a scallop can be executed smoothly and quickly with good work efficiency without damaging the locking piece.SOLUTION: A locking pin 1 for scallop aquaculture includes: a locking piece 5 having a sharp insertion part 3 in the tip part, and constituting a holding unit of a scallop provided inside this axial direction; a storage part 6c of the locking piece 5 provided in the lower shaft part of the locking part of a shaft part 6 stored when constricting a locking part; and a rope retaining part provided further in the inward part in the shaft direction of the shaft part 6. The locking pin for the scallop aquaculture is integrally formed of each part all together in synthetic resin. The locking pin for the scallop aquaculture is provided with stepped parts 11, 12 becoming alternate in the width direction in
