A laser module including a light emitter, a polarizing and filtering unit, a nonlinear optical crystal, and a first filter is provided. The light emitter emits a first beam. The polarizing and filtering unit is disposed on a transmission path of the first beam. A part of the first beam passes through the polarizing and filtering unit to become a second beam with a specific polarization direction. The nonlinear optical crystal is disposed on a transmission path of the second beam from the polarizing and filtering unit. The nonlinear optical crystal converts a part of the second beam into a third beam. The first filter is disposed on a transmission path of a non-converted part of the second beam and the third beam from the nonlinear optical crystal. The non-converted part of the second beam is reflected by the first filter. The third beam passes through the first filter.