The PM10 concentrations in the underground should be monitored for the health of commuters on the subway system. Seoul Metro and Seoul Metropolitan Rapid Transit Corporation are measuring several air pollutants regularly. In this paper, the reliability of the instruments using light scattering method is improved with the help of a linear regression analysis technique to measure the PM10 concentrations continuously in the subway stations. In addition, an USN monitoring system is implemented to display and record the data of PM10, CO/CO2, humidity, and temperature. To transmit and receive these measured sensor data, 2.4GHz Zigbee and 424MHz wireless communication are applied and evaluated.