A light emitting device includes a body, and a lampshade, a heat dissipation device and an adjusting plate are disposed on the body. The lampshade covers a light emitting diode (LED) module of the body and is capable of rotating relative to the body. The heat dissipation device has a plurality of heat dissipation fins covering a part of a lower edge of the lampshade, and a gap exists between two adjacent heat dissipation fins. The adjusting plate corresponds to the lower edge of the lampshade, and can be driven by the lampshade to adjust the width of the gap, so as to control a light profile generated by the light emitting device.