Rare-earth　(RE)　doped　silica　glass　is　essential　for　constructing　high-power　fiber　lasers.　However,　the　achievement　of　high　doping　concentrations　with　a　uniform　RE　ion　dispersion　in　the　SiO2　glass　matrix　is　hindered　by　clustering　and　inhomogeneous　distribution.　Herein,　a　novel　technique-UV-curable　nanocomposite　technology　(UVCNCT)-is　demonstrated　for　fabricating　a　nanoporous　silica　rod　with　a　high　doping　concentration　and　uniform　dispersion　of　RE　ions　in　a　SiO2　glass　matrix.　A　preform　with　an　Yb-doped　P2O5-Al2O3-SiO2　core　and　pure　SiO2　cladding,　and　a　single　cladding　fiber　with　a　doping　concentration　of　2.1　wt%　(for　Yb2O3)　are　fabricated.　A　linear　all-fiber　resonant　cavity　is　constructed　to　analyze　the　laser　performance.　Experimental　results　reveal　the　highly　uniform　dispersion　of　dopants　at　a　relatively　high　concentration　for　both　the　preform　and　fiber　without　aggregation,　center　dip.　The　proposed　technology　is　expected　to　be　an　effective　approach　for　the　fabrication　of　highquality　RE-doped　silica　glass　for　advanced　fiber　lasers.