Nanocrystalline　SnO2　powders　had　been　synthesized　by　the　citrate-gel　method　using　SnCl2　and　citric　acid　as　precursors　and　anhydrous　ethanol　as　solvent.　The　complexation　and　structures　of　the　derived　powders　were　characterized　by　FT-IR,　XRD　and　TEM　techniques.　The　results　show　that　the　tin　citrate　formed　during　the　synthesis　process　with　structure　mainly　in　two-tooth　complexing　and　partly　in　bridge　complexing.　The　rutile-type　SnO2　powders　with　sizes　of　uniform　distribution　around　10　nm　and　good　thermal　resistant　properties　were　obtained　after　heat　treatment.