A lighting lamp with an enhanced heat dissipation function, the lighting lamp comprising: a main body which has a fitting hole formed inwardly through a center portion of an upper surface of the main body, a plurality of heat dissipating fins formed along an outer peripheral surface of the fitting hole, and a mounting surface formed on a lower portion of the main body, the mounting surface having a single annular heat dissipating groove or a plurality of annular heat dissipating grooves; an LED module which is installed to be in close contact with the mounting surface formed on the lower portion of the main body and has a plurality of LEDs 31 installed on a bottom surface of the LED module; a cylindrical fastening boss which is fastened by means of a screw to the LED module, which is in close contact with the mounting surface of the main body, while being fitted and coupled through the fitting hole from an upper side of the main body; a connection portion which is adapted to be fitted into and connected to a socket provided on a ceiling, a wall surface, or the like while being fitted and fixed to an outside of an upper portion of the fastening boss; a lens holder 6& which is fitted and coupled to the bottom surface of the LED module so as to be spaced apart therefrom by a predetermined distance and has lenses mounted at positions corresponding to the respective LEDs constituting the LED module so as to diffuse illumination light emitted from the LEDs and irradiate the illumination light; and a ring-shaped fixing cap which is coupled to a lower end of the main body and is fastened to the lower end by means of a screw while enclosing the LED module and the lens holder, wherein the annular heat dissipating groove which is formed on the mounting surface on the main body is formed to protrude upward to have a depth being in contact with the heat dissipation fin, and characterized in that a plurality of protrusion jaws for forming gaps through which external air flows into the ring-shaped fixing cap along an inner peripheral surface of the ring-shaped fixing cap are formed at regular intervals. a main body which has a fitting hole formed inwardly through a center portion of an upper surface of the main body, a plurality of heat dissipating fins formed along an outer peripheral surface of the fitting hole, and a mounting surface formed on a lower portion of the main body, the mounting surface having a single annular heat dissipating groove or a plurality of annular heat dissipating grooves; an LED module which is installed to be in close contact with the mounting surface formed on the lower portion of the main body and has a plurality of LEDs 31 installed on a bottom surface of the LED module; a cylindrical fastening boss which is fastened by means of a screw to the LED module, which is in close contact with the mounting surface of the main body, while being fitted and coupled through the fitting hole from an upper side of the main body; a connection portion which is adapted to be fitted into and connected to a socket provided on a ceiling, a wall surface, or the like while being fitted and fixed to an outside of an upper portion of the fastening boss; a lens holder 6& which is fitted and coupled to the bottom surface of the LED module so as to be spaced apart therefrom by a predetermined distance and has lenses mounted at positions corresponding to the respective LEDs constituting the LED module so as to diffuse illumination light emitted from the LEDs and irradiate the illumination light; and a ring-shaped fixing cap which is coupled to a lower end of the main body and is fastened to the lower end by means of a screw while enclosing the LED module and the lens holder, wherein the annular heat dissipating groove which is formed on the mounting surface on the main body is formed to protrude upward to have a depth being in contact with the heat dissipation fin, and characterized in that a plurality of protrusion jaws for forming gaps through which external air flows into the ring-shaped fixing cap along an inner peripheral surface of the ring-shaped fixing cap are formed at regular intervals.