A light emitting module including a driving unit and a light emitting diode is provided. The light emitting diode is electrically connected to the driving unit and the driving unit provides an operating current to make the light emitting diode emit light. The light emitting diode includes an n-type semiconductor layer, a light-emitting layer, an electron-blocking layer, and a p-type semiconductor layer. The electron-blocking layer has a thickness, and the thickness is smaller than or equal to 30 nm or is larger than or equal to 80 nm. The light-emitting layer is located between the electron-blocking layer and the n-type semiconductor layer. The electron-blocking layer is located between the p-type semiconductor layer and the light-emitting layer. A ratio of current density of the light emitting diode to the thickness is larger than 0 and is smaller than or equal to 2.