This study is to develop the polymerization inhibitor PI-03 formula by combining chemical with the process technology, and applied in CPC No.5 butadiene plant. Free radicals produced in the system can be easily captured by the inhibitor PI-03 with stable free radical of nitroxide, so the progress of polymerization could be terminated. Under strict monitoring, with the assistance of several improvement actions and plant colleague's efforts, the polymer fouling of the process was reduced, and the frequency of clear-up of heat exchangers was decreased. The average production rate of butadiene can reach as high as 6,400 tons/month. Since plant started up in October 2008 this run, the butadiene plant has been operated continuously over 35 months without any shutting down, which is also the highest operational record of butadiene plants in the company.