Fourier transform infrared spectroscopy (FTIR) technology has become an effective method for monitoring trace gas composition in atmosphere. The dynamic auto-collimation open FTIR system devoloped by Anhui Institute of Optics and Fine Mechamics, CAS, has been used to continuously monitor the atmospheric trace gases in the chemical industrial park in Qingyang city, Gansu Province, China. Continuous monitoring was carried out and compared with the monitoring data of foreign open FTIR instruments under the same conditions. The results show that the open FTIR can monitor the pollution gas components in the chemical park on-line in real time, and provide a scientific monitoring method for environmental pollution control supervision. The domestic open FTIR is superior to the corresponding open FTIR instruments from other foreign countries in terms of signal-noise ratio.