Geosmin　(GSM)　and　2-methyl　isoboneol(2-MIB)　are　the　major　compounds　causing　the　odor　of　water　body.　A　new　method　for　the　qualitative　and　quantitative　analysis　of　GSM　and　2-MIB,　which　isolated　and　enriched　the　odor　compounds　from　the　water　samples　by　using　Headspace　solid-phase　micro　extraction　(HS-SPME),　and　detected　the　two　substances　using　GC/MS　with　internal　standard　method,　was　developed.　The　optimal　conditions　of　HS-SPME　for　GSM　and　2-MIB　were　as　follow:　extracting　for　40minute,　extracting　at　65°C,　and　adding　NaCl　0.1g.　The　temperature　program　for　column　of　GC　was　first　maintained　at　50°C　for　1　minute,　then　rose　to　100°C　at　the　rate　of　10°C　per　minute　keeping　for　0.15minute,　finally　rose　to　240°C　by　5°C　per　minute.　Under　these　conditions,　the　separate　detection　limits　of　GSM　and　2-MIB　were　obtained　with　0.2ng　/　L　and　0.5ng　/　L.　The　relative　standard　deviations　were　5.37%　and　5.56%　respectively.　This　method　applied　for　measuring　the　actual　water　samples　of　Longtan　Lake　and　Taihu　Lake　in　December.　The　former　contained　1.26ng/L　of　GSM　and　1.074ng/L　of　2-MIB,　while　the　latter　included　2.681ng/L　of　GSM　and　3.392ng/L　of　2-MIB.　©2010　IEEE.