The present invention discloses a padlock, comprising a lock cylinder rotatable between a lock position and an unlock position with rotation of a key. The lock cylinder comprises a keyhole, at least one first through hole extending along a first direction for housing at least one first pin, and at least one second through hole extending along a second direction for housing at least one second pin. When the key is in the keyhole, the teeth of the key are aligned with the at least one first pin and the at least one indentations are aligned with the at least one second pin, allowing the lock cylinder to rotate between the lock position and the unlock position with rotation of the key.