A light emitting device capable of performing optimum temperature control of an LED in accordance with each of a plurality of photographing assist uses and sufficiently exhibiting performance of each of uses while ensuring reliability of the LED. The light emitting device includes an LED configured to assist photographing of an image capturing apparatus and a temperature sensor. The light emitting device operates at least in one of a first light emission mode in which a light emission time in one lighting operation of the LED is a first time period and a second light emission mode in which the light emission time is a second time period shorter than the first time period. Different light emission controls are performed on the LED between the first light emission mode and the second light emission mode based on temperature information detected by the temperature sensor.