A laser projection unit, a depth camera and an electronic device are provided. The laser projection unit includes a light source, a collimation element and a diffractive optical element. The light source is configured to emit laser. The collimation element is configured to collimate the laser. The collimation element includes one or a plurality of lenses provided in a light emitting path of the light source. The diffractive optical element is configured to diffract the laser collimated by the diffractive collimation element to form a laser pattern.