The invention discloses an improved art knife guide rail for preventing knife breaking. The improved art knife guide rail comprises a knife shell body with an upward opening, a pushing button, a knifebody and a knife body protecting assembly, wherein a guide rail body is arranged in an inner cavity of the knife shell body, the pushing button is arranged in the guide rail, the knife body is connected with the guide rail body in a sliding manner through the pushing button, and the knife body protecting assembly arranged on the periphery of the knife body in a sleeving manner. The knife body protecting assembly is formed by a first installing plate, a second installing plate and a third installing plate. According to the improved art knife guide rail for preventing knife breaking, on the premise of ensuring the use quality of the knife body, suitability between the guide rail for the art knife body and the knife body is effectively improved, then the situations that in the using process,the knife body is damaged easily, and safety accidents are caused easily can be effectively avoided, and thus the use precision of the guide rail is effectively improved. In addition, by arranging the knife body protecting assembly, the knife body can be protected, the use flexibility of the art knife body is improved conveniently, and therefore the use precision of the knife body of the arc knife is effectively ensured.