The invention provides pipeline prefabrication system. The pipeline prefabrication system comprises a beveling machine, an automatic ink-jet printing machine, a pipeline assembling device and a welding machine. A conveying roller bed is arranged on the inlet side of the beveling machine, and an output roller bed is arranged on the outlet side of the beveling machine. The other side of the output roller bed is connected with the pipeline assembling device. The automatic ink-jet printing machine is arranged above the output roller bed. The welding machine is arranged in the outlet direction of the pipeline assembling device. According to the pipeline prefabrication system, continuous production and manufacturing can be achieved, a lifting platform of the pipeline assembling device and a movable platform with the height being adjustable can meet the matching requirement of various beveling machines, and pipeline prefabrication through integration of the existing beveling machine, the automatic ink-jet printing machine and the welding machine is achieved, and the pipeline prefabrication demand is met. The pipeline assembling device assembles pipe fittings with pipelines through the movable platform and a rotary platform, and the height of the pipe fittings and the pipelines can be adjusted through a hydraulic lifting cylinder, so that assembling is easier, the assembling cost is low, operation is simple and convenient, and the construction efficiency is high.