A cautery pen cover can cover a cautery pen, with little modification thereto, such that the cover must be retracted to both expose the tip and the trigger of the cautery pen. The cover is designed as a protective sleeve that prevents actuation of the cautery pen trigger until the cover is retracted. The cover automatically returns to the covered position when it is released. The cover is always on the cautery pen, whether in use or just lying on the operating field, thereby not requiring users to place and secure the cautery pen in a plastic holster. The cautery pen use various energy sources, such as electro or radio frequency, or any other source that results in cautery or cutting of tissue.
