The system built is a prototype for the security of homes, warehouses or other places to be monitored, as for the workings of this system, when there is an object in front of the sensor, the system will respond by sending a LOW signal, and then this signal is processed in the NodeMCU and then the output is to turn on the lights and sound the alarm, and furthermore the information in the future can be sent to the server or directly call the owner's phone or call other emergency phone numbers. Keywords: infrared, infrared, avoid obstacle, home security, object detection, nodemcu.