The invention provides a front wall assembly structure of a heavy truck cab. The front wall assembly structure comprises a front wall assembly. The front wall assembly comprises a front wall inner plate and a front windshield lower beam. The front wall assembly further comprises a left front wall outer plate, a right front wall outer plate and a middle front wall outer plate through which the left front wall outer plate and the right front wall outer plate are connected. The left front wall outer plate and the right front wall outer plate are fixedly connected with the front windshield lower beam, and the left front wall outer plate, the middle front wall outer plate and the right front wall outer plate are fixedly connected with the front wall inner plate. The left front wall outer plate and the front wall inner plate are provided with corresponding brake valve assembly containing holes. First installing holes are formed in the edges of the brake valve assembly containing holes. The right front wall outer plate and the front wall inner plate are provided with corresponding integrated electrical box containing holes, and second installing holes are formed in the edges of the integrated electrical box containing holes. According to the front wall assembly structure of the heavy truck cab, a brake valve assembly and an integrated electrical box are maintained conveniently.