Three-phase　hollow　fiber-mediated　liquid-phase　microextraction　followed　by　HPLC　was　used　for　the　determination　of　three　synthetic　estrogens,　namely　diethylstilbestrol,　dienestrol,　and　hexestrol,　in　wastewater.　Extraction　conditions　including　organic　solvent,　volume　ratio　between　donor　solution　and　acceptor　phase,　extraction　time,　stirring　rate,　donor　phase　and　acceptor　phase　were　optimized.　The　target　compounds　were　extracted　from　a　10　mL　aqueous　sample　at　pH　1.5　(donor　solution)　through　a　45　min　in　length　hollow　polypropylene　fiber　that　was　immersed　in　1-octanol　in　advance,　and　then　the　hollow　fiber　was　filled　with　10　μL　0.5　mol/L　sodium　hydroxide　solution　(acceptor　phase).　After　a　40　min　extraction,　the　acceptor　phase　was　directly　injected　into　an　HPLC　system　for　detection.　Under　the　optimized　extraction　conditions,　a　large　enrichment　factor　(more　than　300-fold)　was　achieved　for　the　three　estrogens.　The　determination　limit　at　an　S/N　of　3　ranged　from　0.25　to　0.5　μg/L　for　the　estrogens.　The　recovery　ratio　was　more　than　86%　in　the　determination　of　these　estrogens　in　wastewater.　©　2008　Wiley-VCH　Verlag　GmbH　&　Co.　KGaA,　Weinheim.