OBJECTIVE： To investigate the effects of hydrophilic polymers on the stability of self-microemulsifying drug delivery systems （SMEDDS）. METHODS： Taking felodipine （FDP） as model drug， the content of FDP was determined by HPLC method. The effects of pure water， 0.5％ Kollidon VA64， HPMC E5， HPMC K100LV， HPMC K4M， PVP K30 solution， while 0.1％， 0.5％ and 1.0％ HPMC E5 and Kollidon VA64 on residual content of dissolved FDP were determined in SMEDDS. RESULTS： The residual contents of dissolved FDP in SMEDDS placed in Kollidon VA64， HPMC E5， HPMC K100LV， PVP K30， HPMC K4M and pure water for 1 h were 92.7％， 63.6％， 50.2％， 46.2％， 36.0％ and 24.0％， respectively. The order of maintaining the supersaturation state was Kollidon VA64＞HPMC E5＞HPMC K100LV＞PVP K30＞HPMC K4M＞pure water. The residual contents of dissolved FDP in SMEDDS placed in 0.1％， 0.5％， 1％ Kollidon VA64 and HPMC E5 and pure water for 1 h were 93.2％， 95.1％， 96.0％ and 48.4％， 62.1％， 75.1％. CONCLUSIONS： Kollidon VA64 and HPMC E5 can significantly inhibit drug release in SMEDDS and be used as stabilizer of SMEDDS， wherein Kollidon VA64 was better.