Garden shears that avoid loosening of a shaft pin has shears having overlapped first and second cutting members, the first cutting member and second cutting member respectively connected to a first handle and a second handle. The first and second cutting members are secured with the shaft set. The shaft set has a threaded shaft pin, a washer, a threaded securing member and at least two engaging members. when the shears are assembled with the shaft set, the threaded securing member respectively has one engaging member on each side, and the engaging teeth of the threaded securing member engage with the two engaging members to prevent the threaded securing member from loosening due to the repeated opening and closing movements of the shears, and which can improve the smoothness of the operation of the shears and increase both safety and convenience.
