The invention discloses a screen printing machine and provides a divisional application of a special color printing ink addition device for the screen printing machine. The application date of the divisional application is December 7th, 2016 in China, and the application number is 2016111165134. The screen printing machine comprises an ink distribution cylinder and a cleaning cylinder, an ink conveying pipeline is arranged between the end of the ink distribution cylinder and the end of the cleaning cylinder, a plurality of ink supply pipes are arranged on the lower portion of the ink conveyingpipeline, the lower end of each ink supply pipe is a free end, and the upper ends of the ink supply pipes are connected with the ink conveying pipeline; a feeding cylinder is disposed at the end of the ink distribution cylinder, a feed inlet is formed in the end of the feeding cylinder, a diluent tank is arranged on the outer side wall of the end of the ink distribution cylinder, a driving motoris disposed at the end of the ink distribution cylinder, a driving shaft is arranged on the lower portion of the driving motor, stirring blades are arranged at the lower end of the driving shaft, a printing ink delivery pipeline is arranged in the ink distribution cylinder, and the upper end of the printing ink delivery pipeline is connected with one end of the ink conveying pipeline; the cleaningcylinder is internally provided with a cleaning solution conveying pipeline, and the upper end of the cleaning solution conveying pipeline is connected with the other end of the ink conveying pipeline.