Abstract: Fourier transform infrared spectroscopy (FTIR) is widely used in the field of on-line flue gas monitoring due to its advantages such as high response speed, wide measuring range, low maintenance cost and traceless detection. However, due to the high technical difficulty, imported equipment has occupied a high market share for a long time. In order to break the situation, an on-line Fourier transform infrared gas analyer based on Fourier transform technology has been developed. Through comparison and verification, the performance of the self-made equipment has basically reached the same level as that of the imported mainstream equipment. In order to further verify the actual usage, the performance of the gas was verified respectively in the laboratory and at the waste incineration site, and the verification results were far better than the index requirements of the relevant standards. In addition, during the continuous operation of the equipment for 15 months, the measurement results were monitored in real time, and the long-term comparison was made with the SICK FT of the same outlet. The long-term measurement trend and measurement results were highly consistent, which fully demonstrated that the analyzer has high accuracy and reliability when measuring actual flue gas, meeting the requirements in the field of on-line monitoring for waste incineration.