OBJECTIVE：To compar e the absorpt ion characteristics of gastrodin ，parishin A ，parishin B and parishin C of Gastrodia elata powder，and to explore the effect of particle size on intestinal absorption of above components. METHODS ：Based on everted intestinal sac model ，using accumulative absorption amount （Q）and absorption rate constant （Ka）as indexes ，UPLC-MS/MS method was used to determine the absorption of gastrodin ，parishin A ，parishin B and parishin C from different doses （2.5，5，10 g/L） of G. elata powder with different particle sizes （fine powder 146 μm，superfine powder 52 μm，ultrafine powder 37 μm）in different segments（duodenum，jejunum，ileum and colon ）. RESULTS ：Q and Ka of gastrodin and parishin B （intestinal segment ），Q（colon） and Ka（ileum and colon ）of parishin C in 2.5 g/L G. elata superfine powder ；Q and Ka of gastrodin （intestinal segment ），Q and Ka of parishin B （duodenum，jejunum，ileum）and Ka of parishin C （colon）in 2.5 g/L G. elata ultrafine powder ；Q of gastrodin （duodenum），Q of parishin A and parishin B （intestinal segment ）and Q of parishin C （duodenum，jejunum）in 5 g/L G. elata superfine powder ；Q（duodenum jejunum ，colon）and Ka（intestinal segment ）of gastrodin ，Q of parishin B （duodenum，ileum and colon）and Q of parishin C （duodenum，ileum）in 5 g/L G. elata ultrafine powder ；Q and Ka of parishin B （jejunum，ileum），Q of parishin C （jejunum，ileum）in 10 g/L G. elata superfine powder as well as Q（colon）and Ka（duodenum）of gastrodin ，Q （duodenum，ileum，colon）and Ka（duodenum，colon）of parishin B ，Q（duodenum，ileum）and Ka（duodenum）of parishin C in 10 g/L G. elata ultrafine powder were all increased significantly ，compared with the same dose of G. elata fine powder （P＜0.05 or P＜0.01）. Ka of parishin A （jejunum）and Q of parishin C （duodenum）in 2.5 g/L G. elata superfine powder ；Ka of parishin A （jejunum，ileum）， Q and Ka of parishin C （duodenum，jejunum）in 2.5 g/L G. elata ultrafine powder ；Ka of gastrodin （jejunum，ileum and colon ），Ka of parishin A （colon），Ka of parishin B （ileum）and Ka of parishin C （jejunum，ileum）in 5 g/L G. elata superfine powder ；Ka of gastrodin and parishin C （jejunum，ileum and colon ），Q（jejunum，colon）and Ka（colon）of parishin A ，Ka of parishin B （jejunum，ileum）in 5 g/L G. elata ultrafine powder ；Q and Ka of parishin A （ileum）in 10 g/L G. elata superfine powder ；Q（duodenum）and Ka（jejunum） of parishin A ，Ka of parishin C （jejunum）in 10 g/L G. elata ultrafine powder were decreased significantly ，compared with the same dose of G. elata fine powder （P＜0.05 or P＜0.01）. Q of gastrodin （colon），Q（colon）and Ka（ileum，colon）of parishin A ，Q and Ka of parishin B （jejunum，colon），Q and Ka of parishin C （ileum，colon）in 2.5 g/L G. elata fine powder ；Q and Ka of gastrodin （colon），Q（ileum，colon）and Ka（jejunum，ileum，colon）of parishin A ，Ka of parishin C （colon）in 2.5 g/L G. elata superfine powder；Q（colon）and Ka（jejunum，ileum，colon）of parishin A and C ，Q and Ka（ileum，colon）of parishin B in 2.5 g/L G. elata ultrafine powder ；Q and Ka of gastrodin ，parishin A and C （colon），Ka of parishin B （colon）in 5 g/L G. elata fine powder ；Q and Ka of gastrodin and parishin A （colon），Q and Ka of parishin C （jejunum，ileum，colon）in 5 g/L G. elata superfine powder ；Q and Ka of gastrodin（ileum，colon），Q of parishin A （jejunum，ileum，colon），Q and Ka of parishin B （jejunum，colon），Q（jejunum，colon） and Ka（jejunum，ileum，colon）of parishin C in 5 g/L G. elata ultrafine powder ；Q of gastrodin （colon），Q and Ka of parishin A ，B and C （jejunum，ileum，colon）in 10 g/L G. el ata fine powder ；Q of gastrodin （colon），Q and Ka of parishin A and C （jejunum， ileum，colon），Q and Ka of parishin B （colon）in 10 g/L G. elata superfine powder ；Q（colon）and Ka（jejunum，ileum，colon）of gastrodin，Q and Ka of parishin A and C （jejunum，ileum，colon），Q（jejunum，ileum，colon）and Ka（ileum，colon）of parishin B in 10 g/L G. elata ultrafine powder were decreased significantly ，compared with duodeum of the same group （P＜0.05）. Q and Ka of gastrodin（jejunum）in 2.5 g/L G. elata superfine pow