An outdoor lighting device for lighting a target, particularly for use in street lighting, comprising: a support structure; a lighting unit (3,103) stably associated with said support structure; one or more reflecting surfaces (5,205) defining a hollow body having an outwardly directed aperture; and one or more light beam sources of the LED type having predetermined FWHM values of the respective luminous spectrum, said LED sources being arranged into said hollow body to direct said light beams toward said reflecting surfaces (5,205); said outwardly directed aperture facing toward a target, all of said reflecting surfaces (5,205) being arranged into the interior space of said hollow body and being so shaped that at least one of said LED sources has the FWHM of its luminous spectrum totally reflected by at least one of said reflecting surfaces (5,205) and totally projected towards a target, for increased lighting efficiency of the device; said one or more reflecting surfaces (5,205) including first reflecting surfaces and second reflecting surfaces; characterized in that said LED sources are arranged along the peripheral borders of said hollow body and facing said first reflecting surfaces and said second reflecting surfaces; said second reflecting surfaces are planar, being arranged centrally with respect to said hollow body and being converging towards said outwardly directed aperture; said second reflecting surfaces being susceptible of reflecting the light beams that impinge upon them towards the target; in that said first reflecting surfaces are susceptible of reflecting the light beams that impinge upon them towards the target and/or towards said second reflecting surfaces, in that said first reflecting surfaces comprise a first set of reflecting surfaces acting as a collector for the light beams emitted from said at least one LED source and as a projector that directs some of these beams directly towards the target, and in that said second reflecting surfaces comprise a second set of reflecting surfaces only acting as a projector and deflecting all the collected beams transmitted thereto from said first set towards the target. a support structure; a lighting unit (3,103) stably associated with said support structure; one or more reflecting surfaces (5,205) defining a hollow body having an outwardly directed aperture; and one or more light beam sources of the LED type having predetermined FWHM values of the respective luminous spectrum, said LED sources being arranged into said hollow body to direct said light beams toward said reflecting surfaces (5,205); said outwardly directed aperture facing toward a target, all of said reflecting surfaces (5,205) being arranged into the interior space of said hollow body and being so shaped that at least one of said LED sources has the FWHM of its luminous spectrum totally reflected by at least one of said reflecting surfaces (5,205) and totally projected towards a target, for increased lighting efficiency of the device; said one or more reflecting surfaces (5,205) including first reflecting surfaces and second reflecting surfaces; characterized in that said LED sources are arranged along the peripheral borders of said hollow body and facing said first reflecting surfaces and said second reflecting surfaces; said second reflecting surfaces are planar, being arranged centrally with respect to said hollow body and being converging towards said outwardly directed aperture; said second reflecting surfaces being susceptible of reflecting the light beams that impinge upon them towards the target; in that said first reflecting surfaces are susceptible of reflecting the light beams that impinge upon them towards the target and/or towards said second reflecting surfaces, in that said first reflecting surfaces comprise a first set of reflecting surfaces acting as a collector for the light beams emitted from said at least one LED source and as a projector that directs some of these beams directly towards the target, and in that said second reflecting surfaces comprise a second set of reflecting surfaces only acting as a projector and deflecting all the collected beams transmitted thereto from said first set towards the target.