Urban　area　detection　from　the　remote　sensing　imagery　has　important　significance　in　dynamic　monitoring　on　the　use　types　of　city　land　and　the　city　development　planning.　An　approach　for　full-automatic　detection　of　urban　area　is　proposed,　which　can　fuse　any　number　of　features.　The　combination　formula　of　the　traditional　D-S　evidence　theory　(TDSET)　is　improved　by　adding　a　processing　factor　for　conflicting　evidences　based　on　the　original　fusion　function.　For　the　validity　of　the　proposed　method,　three　positive　evidences　(gradient　mean,　Harris　feature　points　and　spectral　homogeneity)　as　well　as　one　negative　evidence　(local　gradient　orientation　density)　are　selected　to　test　three　GeoEye　images.　Experimental　results　show　that　the　precision　of　the　proposed　method　achieves　96.89%　and　its　recall　is　86.52%,　where　the　recall　increases　about　50%　comparing　with　the　TDSET.