A wearable illumination activity recording apparatus (1) includes a processing unit (11), a light sensing unit (12) and a motion sensing unit (13). The light sensing unit (12) is electrically connected to the processing unit (11) and outputs a light sensing signal (LS) to the processing unit (11). The motion sensing unit (13) is electrically connected to the processing unit (11) and outputs a motion sensing signal (MS) to the processing unit (11). The processing unit (11) determines whether the wearable illumination activity recording apparatus (1) is indoors or outdoors according to the light sensing signal (LS), and determines whether the wearable illumination activity recording apparatus (1) is in motion or not according to the motion sensing signal (MS). When the wearable illumination activity recording apparatus (1) is outdoors and in motion, the processing unit (11) records an illumination-receiving time.