The　Xiaodong　Sb　deposit　in　Wenshan　Prefecture,　Yunnan　Province,　is　located　in　the　southeastern　Yunnan　Sb　metallogenic　belt.　The　Sb　ore　body　is　present　in　siliceous　rocks　located　in　the　lower　section　of　the　Tianpeng　Formation,　Middle　Cambrian.　Although　previous　studies　proposed　that　it　is　a　hydrothermal　sedimentary　Sb　deposit　formed　via　metamorphism,　its　petrogenesis　and　metallogenic　mechanisms　still　remain　unclear.　This　study　performs　major　and　trace　element　analysis　of　the　siliceous　rocks,　and　the　results　show　w(SiO2).content　of　84.70%～　97.11%　(average　of　92.19%),　while　the　w(Al2O3).has　a　content　of　0.63%～　6.08%　(average　of　3.56%）.　ΣREE　ranges　from　20.43×10-6to　77.54×10-6,　showing　an　enrichment　of　LREE　and　a　depletion　of　HREE,　with　δEu　(0.66～1.57).and　δCe　(0.95～1.15）.　The　results　reveal　that　the　siliceous　rocks　formed　by　non-hydrothermal　sedimentation　in　the　continental　margin　and　they　originated　in　terrestrial　sources.　An　LA-ICP-MS　analysis　of　trace　elements　in　the　stibnite　shows　that　the　main　substitution　mechanism　is　2Sb3+↔As3++(Cu++Pb2+）.　The　δ34S　value　of　stibnite　(0.42‰　to　4.91‰).shows　the　signature　of　magmatic　sulfur,　implying　that　the　mineralized　hydrothermal　fluids　maybe　related　to　the　Laojunshan　intrusion　or　deep,　hidden　magmatic　rocks.　The　comprehensive　analysis　presented　here　shows　that　the　Xiaodong　deposit　is　not　related　to　hydrothermal　sedimentation;　instead,　the　mineralized　material　mainly　came　from　magmatic　hydrothermal　fluid,　which　enriched　the　interlayer　fracture　belt　during　a　late　stage　of　magmatic　activity.　This　study　characterizes　the　deposit　as　a　fault-controlled　hydrothermal　Sb　deposit.　©　2025,　Chengdu　University　of　Technology.　All　rights　reserved.