The application relates to a lock with high safety, which enhances the safety of the lock through a simple structure. Specifically, the lock comprises a lock cylinder and a key. The lock cylinder comprises a lock shell, the lock shell comprises a lock shell connecting portion installation cavity, a main ball locking
assembly which can be telescopically arranged in the lock cylinder along the vertical direction is arranged between the lock shell connecting portion and the lock cylinder, a special-shaped magnetic ball locking
assembly which can be telescopically arranged in the lock cylinder is arranged between the installation cavity inner wall surface and the lock cylinder in the axial direction, the main ball locking
assembly and the special-shaped magnetic ball locking assembly are used for locking and releasing the circumferential limiting between the lock cylinder and the lock shell; the key is provided with a first tooth opening corresponding to the main ball locking assembly, and the key is further provided with a first
magnet corresponding to the special-shaped magnetic ball locking assembly; when the key is inserted into the key hole, the upper end of the main ball locking assembly is correspondingly inserted into the first tooth opening, and the special-shaped magnetic ball locking assembly is attracted into the lock cylinder by the first
magnet; at this time, the key can be rotated to drive the lock cylinder to rotate, so that the lock is opened.