The invention discloses a drill bit fracture detecting device which is simple in structure and capable of carrying out centralized measurement. The drill bit fracture detecting device comprises a mounting barrel which is vertically arranged and can vertically move, wherein the mounting barrel comprises an upper straight barrel and a lower expansion barrel with an end cover; outgoing lines which are connected with a controller are arranged in the straight barrel in a penetrating way; an accommodating cavity is formed in the expansion barrel; an insulation plate is arranged in the accommodating cavity; the accommodating cavity is divided into an upper cavity and a lower cavity by the insulation plate; binding posts are arranged on the insulation plate in a penetrating way; the upper ends of the binding posts are connected with the outgoing lines; the lower ends of the binding posts stretch into the lower cavity; measuring needles which can vertically move are arranged on the end cover in a penetrating way; and the upper ends of the measuring needles are in contact with the lower ends of the binding posts.