The first Shanghai Metro Line began operation in April 1995, and 14 subway lines with 366 stations were operating as of December 2015. The length of the subway network now totals about 617 km. The passenger flow is more than 9 million people daily, and the number is increasing year by year. Therefore, it is important to obtain information about the air quality in Shanghai’s subway system and its potential influence on these passengers. As a result, some scholars have studied the environmental quality in the Shanghai metro. It is also worth noting that after the subway station has been built, many characteristics of the station cannot be easily changed. However, our study provided some consistent findings that suggest ways to minimize health damage caused by air pollution in the subway.