The invention discloses a magnetic core lock. The magnetic core lock comprises a lock structure mounting plate, a spring mounting plate, a lock tongue base, compression springs, a sliding lock cylinder, a lock structure box, a magnetic core key, a sliding guide hole, a pair of spring limiting columns, a lock tongue part, an inclined ridge type sliding groove, spring clamping columns, a traction magnetic block and an inclined ridge type sliding block, and the inclined ridge type sliding block is arranged in the inclined ridge type sliding groove in a matched manner. The lock structure box is fixed to the back face of the lock structure mounting plate, the sliding lock cylinder and the lock tongue base are contained in the lock structure box, and an attraction magnetic block is arranged at the front end of the magnetic core key. By means of the magnetic characteristic that the magnetic core key and the traction magnetic block attract each other, the lock tongue part of the lock tongue base can be driven to complete telescopic motion by pulling up the magnetic core key, and a lock structure is opened; and during management, all lock structures can be opened only through one magnetic core key, and the management efficiency of a cinerary casket is greatly improved.