Objective To investigate the synergistic inhibition effect of zinc nitrate, sodium molybdate and tripolyphosphate and make the property of these inhibitors to complement each other. Methods Based on acidic potassium permanganate solution, the synergistic inhibitive effect of zinc nitrate, sodium molybdate and tripolyphosphate on corrosion of 1Cr18Ni9Ti stainless steel was investigated by means of polarization curve and weight loss method. Results Zinc nitrate and tripolyphosphate could mainly inhibit the cathodic process of 1Cr18Ni9Ti stainless steel, while sodium molybdate mainly suppressed its anodic reaction. Since zinc nitrate and sodium molybdate had significantly antagonism with each other, the effectiveness of corrosion inhibition became poor. These three corrosion inhibitors exhibited a good synergistic effect after tripolyphosphate was added, which lead to the optimal performance of the overall effectiveness of inhibitors and the efficiency of corrosion inhibitor could reach higher than 90% . Conclusion There was a good synergistic effect among zinc nitrate, sodium molybdate and tripolyphosphate in corrosion inhibition of metals. The corrosion rate of 1Cr18Ni9Ti stainless steel could be significantly reduced in acidic potassium permanganate solution and the life of the equipment could be extended.