The disclosure provides an electronic device and a detecting position method adapted for the electronic device. The device stores an infrared sensing mode and a capture mode. The method includes steps of: entering the infrared sensing mode in response to an input signal and capturing infrared signals from an external environment, amplifying the infrared signals and converting the infrared signals into digital signals, evaluating whether part of the infrared signals falls into a predetermined waveband, if yes, focusing on an infrared thermal source whose infrared signals fall into the predetermined waveband, switching from the infrared sensing mode to the capture mode, taking a photo of the infrared thermal source, and processing the photo to identify a position of the infrared thermal source in the photo and displaying the position of the infrared thermal source in the photo.