The invention discloses an ARM temperature and humidity self-correction based electromagnetic radiation measuring device and a measuring method. The ARM temperature and humidity self-correction based electromagnetic radiation measuring device comprises an electromagnetic radiation sampling module, a signal processing module, a temperature and humidity digital sensor, an embedded type micro-processor module, a memorizer and a display module; the embedded type micro-processor module is respectively connected with the signal processing module, the temperature and humidity digital sensor, the memorizer and the display module; the signal processing module is connected with the electromagnetic radiation sampling module. According to the ARM temperature and humidity self-correction based electromagnetic radiation measuring device, environment temperature and humidity influences to a measuring result are considered meanwhile the environmental electromagnetic radiation intensity is measured, the measuring result is corrected in real time through an artificial neural network model, the measuring result authenticity and accuracy is guaranteed, environmental limit to utilization conditions of instruments is effectively widened, measurement can be performed under the severe environment, and the device automatically stops working to avoid instrument damage when the environment temperature and humidity exceeds a threshold value.