A projecting device is provided. The projecting device is adapted to assembling with an electronic device. The projecting device comprises a main body, a light emitting portion, a rotating portion, and an adjusting portion. The main body includes a first opening and a second opening. The light emitting portion is disposed in the main body, and transmits a light through the first opening. The rotating portion is disposed in the main body and connected with the light emitting portion. The adjusting portion is disposed in the second opening and connected with the rotating portion. The light emitting portion drives the rotating portion to rotate through the adjusting portion to adjust the angle of the light.