Beam-carrying gun truck is a precast beam transport machine specially designed for highway bridge erection. It consists of two independent operating mechanisms (active vehicle and passive vehicle). The main vehicle is equipped with a four-cylinder or six-cylinder diesel engine, which provides driving force for the whole vehicle after four-stage deceleration. The final drive is a big gear or planetary gear drive. Set hydraulic steering and air braking functions. Generally, there are multiple forward gears and reverse gears. The auxiliary vehicle is equipped with a single-cylinder diesel engine to provide power for hydraulic steering. The invention has the functions of transporting beams and feeding beams to the bridge erecting machine, and is mainly suitable for bridge construction sites and prefabricated beam yards.