The invention relates to the technical field of three-way pipe pretreatment devices, in particular to a pretreatment system for infusion apparatus three-way pipes before assembly. The pretreatment system for the infusion apparatus three-way pipes before assembly comprises a rack, and a three-way pipe feeding device, a three-way pipe taking and transferring device, a three-way pipe rotating and aligning device and a three-way pipe overturning device which are arranged on the rack, the three-way pipe feeding device and the three-way pipe rotating and aligning device are sequentially installed on the rack, the three-way pipe taking and transferring device is installed at the part, above the three-way pipe feeding device and the three-way pipe rotating and aligning device, of a body of the rack, and the three-way pipe overturning device is installed at the part, above the three-way pipe rotating and aligning device, of the body of the rack. According to the pretreatment system, a large amount of materials can be fed at a time, the three-way pipes are convenient to align in the feeding process, and the flow continuity of feeding, aligning, grabbing and transferring is high. The devices are compact in structural design, easy to operate, coherent in action and high in assembling precision, and the assembling efficiency of the three-way pipes and a infusion apparatus short pipe is greatly improved.