The invention discloses a double-drill bit tunnel automatic drilling machine and a method. The drilling machine comprises a crawler chassis, a control supporting box, a hydraulic control box, a centersupporting shaft, a transverse shaft, a main oil cylinder, a motor and a double-drill bit mechanism. The method comprises the following steps that 1, a hole position mark is arranged; 2, the drillingmachine carries out automatic drilling in a tunnel section by; 3, the drilling machine carries out tunnel automatic drilling; 4, percussion drill trouble shooting is carried out; and 5, steel bar drill trouble hunting is carried out. According to the double-drill bit tunnel automatic drilling machine and the method, by arranging the double-drill bit mechanism, unnecessary abrasion to a steel bardrill is reduced, and the production cost is reduced; and the working state of the drilling machine is identified through the drilling depth and the drilling speed, whether a steel bar is encounteredor not in the drilling process is detected in time, the drilling is continuously carried out by timely switching the drill bit when the steel bar is encountered, the drilling machine is prevented fromworking in an abnormal state or drilling a non-normal hole, the working reliability is high, and the drilling machine is convenient to popularize and use.