The present invention relates to a kind of disposable scalpel blade assembly and supporting reusable scalpel handle. The blade assembly consists of a blade, blade holder and blade shield wherein 1. The blade holder is provided with a flexible arm at the rear end. The flexible arm is provided with a protrusion block at the end of the flexible arm. The inner wall of the blade shield is provided with a clearance opening for said protrusion block. When the handle is inserted, the protrusion block extends into the clearance opening with a sideward movement, so that the blade and the blade holder are connected. But after the handle is pulled out, the protrusion block misaligns with the clearance opening and cannot make sideward movement such that the handle cannot be connected again 2. The first sliding channel of the blade holder is provided with a first front locking channel at its front end and a deadlock channel is set in front of the first front locking channel. When the handle is pulled out after use of the scalpel, the first protrusion of the blade shield shall fall into the deadlock channel to enter the deadlocking state. The present invention thoroughly eliminates the safety problem of reusing the scalpel blade.
