The invention belongs to the technical field of mechanical parts manufacturing, and particularly relates to a manufacturing method of a brake tube of an air brake system. The manufacturing method of the brake tube of the air brake system comprises the following steps of smelting molten steel, casting into die casting billet, electroslag remelting, cogging hot rolling into square billet, forging into round ingots, hot extrusion, lubrication cold rolling, annealing treatment, surface treatment, inspection and entering a storage; in the process of smelting molten steel, the molten steel is produced when the composition of the molten steel meets the following requirements, wherein the molten steel is prepared from the following components in percentage by weight: 0.02%-0.03% of C, 0.018%-0.028% of P, 17.2%-17.4% of Cr, 9.2%-9.5% of Ni, 0.001%-0.002% of S, 0.21%-0.28% of Ti, 0.05%-0.06% of N, 0.01%-0.15% of Cu, the balance of Fe and unavoidable impurities. According to the manufacturing method of the brake tube of the air brake system, through the special design of material ingredients and optimization of partial parameters and methods of hot extrusion, lubrication cold rolling, annealing treatment, surface treatment and the other processes, so that the brake tube of the air brake system has better corrosion resistance and surface quality.