Abstract: A study on elimination of residues of thiamphenicol (TAP) was conducted in egg white, egg yolk and whole egg of laying hens. TAP was extracted from eggs of laying hens with alkalized ethyl acetate. The extract solution was degreased in n-hexane saturated with acetonitrile, dried in nitrogen evaporator and residues were dissolved in mobile phase. TAP was determinated by high performance liquid chromatography (HPLC) with fluorescence detector. The lowest limit of detection（LOD） was all 1.5 μg·kg^-1(S/N=3) for TAP in egg white, egg yolk and whole egg and the lowest limit of quantitation(LOQ) was all 5 μg·kg^-1(S/N=10) for TAP. After the laying hens orally administered successively Tap capsules of 10.0, 20.0 and 50.0 mg·kg1 of body weight once every day for 5 days, respectively, residues of TAP in egg white, egg yolk and whole egg have a rise trend. The maximum residue of TAP was detected at the first day after withdrawal time in egg white, egg yolk and whole egg. At the early days after withdrawal time, the residues of TAP in egg white, egg yolk and whole egg were eliminated faster, but they were eliminated slowly at the later period. Residues of TAP in whole egg and egg white were all lower than 50 μg·kg^-1， and the lowest LOD (1.5 μg·kg^-1）at 6th withdrawal day, respectively. Residues of TAP in egg yolk and whole egg were all lower than the lowest LOD (1.5 μg·kg^-1）at 8th withdrawal day. Residues of TAP in egg white, egg yolk and whole egg were positively correlated with TAP orally administered doses

Key words: eggs of laying hens, thiamphenicol (TAP), residue, elimination, HPLC with fluorescence detection