Firstly　we　discussed　the　effect　of　each　variable　factor　on　the　extraction　rate　of　Total　Flavonoids　Compounds　(TFC)　on　the　basis　of　single-factor　experiment,　then　we　screened　the　important　variable　factors　with　respect　to　their　main　effects　on　the　extraction　rate　of　TFC　by　Plackett-Burman　(PB)　design,　and　extraction　temperature,　ethanol　concentration　and　solid-to-liquid　ratio　were　identified　as　the　most　significant　variables.　Next　we　optimized　the　extraction　conditions　including　these　significant　variables　by　Response　Surface　Analysis　(Box-Behnken　(BB)　design)　and　obtained　the　optimum　levels　of　these　significant　parameters　which　revealed　these　as　follows:　ethanol　concentration　of　65%,　ultrasound　temperature　of　65°C,　solid-liquid　ratio　of　1:25.　Under　the　optimum　conditions,　the　predicted　value　of　extraction　rate　of　TFC　is　10.27%　and　its　experimental　value　is　10.29%.　This　result　indicates　that　it　is　perfect　to　optimize　of　extraction　conditions　of　TFC　from　Loguat　Leaves　by　PB　design　and　BB　design.