Abstract: A light emitting module for automatically adjusting the lighting power includes a light emitting diode module and a power control board. The power control board is electrically connected with the light emitting diode module. The power control board further includes a power converting unit and a thermal sensing unit. The thermal sensing unit detects the environmental temperature to generate a measured signal of temperature. The power converting unit converts the first power into a second power to output according to the measured temperature from the thermal sensing unit. Thereby, the lighting power of the light emitting module is automatically adjusted. When the temperature is high, the lighting power is decreased to lower the temperature. When the temperature is low, the lighting power is increased.