Abstract:  The three environmental air quality index evaluation methods, namely the mean value index,weighted index, and N. L. Nemerow index, each have their own advantages and disadvantages. Conduc-ing a comparative evaluation of these three air quality indices can provide valuable insights for improvingenvironmental air quality assessments. By applying the mean value index, weighted index, and N. .Nemerow index to assess the urban air quality of Wenshan City, the results show that, whether comparingmean dilerences or conducting two independent sample tests, the evaluation results ( index values) of themean value index and weighted index are not significantly different. However, the evaluation results ( in-dex values) of the N. L.. Nemerow index differ significantly from both the mean value index and theweighted index (P <0. 05 ). From May to 0etober 2023, 0, was the primary pollutant of urban air pollu-lion in Wenshan City. In the remaining months of 2023, PM,s was the primary pollutant. Over thecourse of the entire year, PM,s emerged as the primary pollutant in Wenshan City's urban air, while 0and PM,, were also significant pollutants. In 2023 , the highest values of the urban air quality index inWenshan City were observed in April, while the lowest values were recorded in july. The urban air quality in Wenshan City worsened gradually from January to April, improved from April to July, and then de-teriorated again from July to December.

Key words: air quality index, mean value index, weighted index;N. L Nemerow index, wenshan