An exemplary light source module includes a printed circuit board (PCB), a heat-dissipating assembly, and a number of light emitting elements. The PCB includes a first surface, an opposite second surface, and a number of through holes. The heat-dissipating assembly is located adjacent to the second surface and includes a base, a number of heat-conducting elements, and a number of heat dissipation fins. The base includes a third surface defining a number of cavities therein and an opposite fourth surface. The heat dissipation fins extend from the fourth surface. Each of the heat-conducting elements is inlaid in a corresponding cavity. Each of the light emitting elements is placed in a corresponding through hole and thermally contacts a corresponding heat-conducting element. Each light emitting element electrically connects with the PCB and defines a respective light emitting surface located outside the corresponding through hole.