The indoor air quality monitoring system is needed to find out good air condition. Good air condition can be seen from two (2) factors, namely dust, and temperature. Dust in a room can affect health if it exceeds the threshold of 0.15 mg/m3, and the temperature of 35oC has been determined by SK MENKLH No.02/MENKLH/I/1998. Related to that, we need a system that can determine the temperature and dust conditions in a room. The aim of this research is creating an indoor air quality monitoring system based on the Internet of Things (IoT). This research uses engineering methods, which include planning, design, testing, and system implementation. In this system, when the dust level is more than 0.15 mg/m3 the LED indicator 1 and the active sprayer tell and neutralize the dust content in the air and when the intensity of the temperature is more than 35oC the LED indicator 2 and the active sprayer tell and neutralize the temperature intensity at the room. When both values exceed the set threshold, the LED indicators 1, LED 2, buzzer, the sprayer will be active simultaneously to notify and neutralize the air and temperature in the room. The test results show this system can work well with the percentage of errors in the testing of 12% for dust sensors and 1.6% for temperature sensors.