An illumination module is disclosed, which is comprised of a plurality of light sources, a plurality of light source substrates of high thermal conductivity, and a reflecting member for reflecting light. The plural light source substrates are arranged at positions corresponding to each other so as to form a polygon periphery of the illumination module, whereas the inner surface of the polygon periphery is enabled for at least one of the plural light sources to fit therein. The reflecting member is placed at the center of the module where it is corresponding to each of the plural light source substrates so as to reflect the light emitting from the light sources fitted thereon. In addition, a lens with light refraction ability is disposed at the light emitting end of the illumination module so as to enable the light illumination module to have light condensing/diffusing capability. Moreover, each light source substrate further comprises: a plurality of heat dissipating fins, being arranged at the outer surface thereof; and a assistant heat dissipating device; wherein the working range of the operation power and the luminous flux of the illumination module can be increased by the combined function provided by the heat dissipating fins and the assistant heat dissipating device. The assistant heat dissipating device can further comprise: a fan, being arranged at the bottom of the illumination module; and a heat pipe device, being fitted onto the light source substrate, for conducting waste heat to the heat dissipating fins to be dissipated.