Fed-batch　cultures　were　carried　out　for　the　degradation　of　phenol　by　Trichosporon　sp.X1.　When　phenol　was　used　as　the　sole　carbon　and　energy　source,　the　suitable　phenol　concentration　was　studied　to　avoid　the　substrate　inhibition.　Exponential　feeding　strategy　with　manual　feedback　was　adopted　to　obtain　higher　cell　concentration.　The　optimal　set　point　of　specific　growth　rate　was　0.4-0.5μmax　(μmax　denotes　the　maximum　specific　growth　rate　from　Haldane　model).　The　exponential　feeding　strategy　with　optimal　substrate　concentration　(110mg/L)　was　found　to　be　more　efficient　since　higher　specific　growth　rate　was　stimulated　by　residual　phenol.　©2009　IEEE.