In order to understand the extinction characteristics of aerosols and gases in Baoji High-Tech Zone, China, the hourly observation data of the nephelometer and aethalometer in Baoji High-Tech Zone in January 2018, as well as the meteorological elements and the mass concentration of PM2.5 and NO2 in the same section, were used to analyze the variation characteristics of extinction coefficient B ext, aerosol scattering coefficient B sp, absorption coefficient B ap and gas absorption coefficient B ag, and then the contribution rate of aerosol extinction coefficient and gas extinction coefficient to atmospheric extinction were evaluated. The results show that, B ext of Baoji High-tech Zone ranges from 200.63～948.87 Mm－1 with a mean value of 483.12 Mm－1, B sp of aerosol ranges from 170.83～890.06 Mm－1 with a mean value of 444.11 Mm－1, while B ap ranged from 4.89～20.44 Mm－1 with a mean value of 9.69 Mm－1. The correlation coefficients of PM2.5 and B ext, B sp and B ap are 0.952, 0.950 and 0.572, respectively, indicating that the influence of PM2.5 in Baoji High-tech Zone on atmospheric extinction can not be ignored. It is also found that the aerosol scattering coefficient B sp is significantly positively correlated with relative humidity (RH) and negatively correlated with visibility. It seems that aerosol scattering and absorption coefficients have significant double peak and double valley diurnal variation characteristics, which is related to Baoji High-Tech Zone’s commuting time and motor vehicle running time. It is also found that Black carbon (BC) mass concentration, B sp and B ap increase as the pollution level increases. The overall analysis shows that the extinction coefficient of aerosol accounts for 93.93% of the total atmospheric extinction coefficient, in which scattering and absorption coefficients accounts for 91.92% and 2.01% respectively, and the extinction coefficient of gases accounts for 6.07% of the total atmospheric extinction coefficient.