The invention discloses an indoor environment monitoring system. In the system, the outputs of a CO sensor circuit, a SO2 sensor circuit, a CH2O sensor circuit, a CO2 sensor circuit, a noise sensor circuit and an electromagnetic radiation sensor circuit are connected with the input of a sensor multipath gating circuit, the output of the sensor multipath gating circuit is connected with the input of an analog-to-digital conversion circuit, the outputs of the analog-to-digital conversion circuit, a temperature-humidity sensor circuit, an inhalable particulate sensor circuit, a reserved interface circuit and a key circuit are respectively connected with the input of a singlechip, the output of the singlechip is respectively connected with an acousto-optic alarm circuit, a liquid crystal display circuit and a reserved expansion I/O port circuit, and a power supply circuit supplies power for the whole system. The system can monitor eight environment pollution-related parameters, intelligently analyze the influences of each parameter on a human body, display a current comfortableness value, and automatically execute relevant operations according to data results, and has convenient operation, high automation degree, high correctness and good safety.