The invention relates to a manufacturing method of a composite pipe band, in particular to a double-layer ribbing two-color composite pipe band production line and a machining method thereof. The double-layer ribbing two-color composite pipe band production line comprises a burdening machine, extrusion equipment and a sizing cooling device that are sequentially connected; and an outlet of the sizing cooling device is detachably connected with a pipe forming mechanism. The double-layer ribbing two-color composite pipe band production line is simple in structure and the input and output modes are single. During machining, simply by inputting calculated amounts of raw materials to the burdening machine, a band output by the production line can be directly warehoused or input to a pipe forming mechanism for use, so that the manufacturing of the band is easier, and the band can be used to manufacture a pipe conveniently; in addition, since the sizing cooling device is arranged between the extrusion equipment and the pipe forming mechanism, the band output from the extrusion equipment is pre-cooled, a situation that interior cavity collapse or reinforcing rib deformation is generated due to the fact that the high-temperature band output from the extrusion equipment is affected by external environment factors like the gravity is avoided, and the band manufactured by the production line meets the use requirements.