Abstract: Fourteen healthy pigs were divided into two groups of 7 pigs each. The pigs in group A were orally administrated with single dose of florfenicol powder at 30 mg/kg. The pigs in group B were also orally administrated with single dose of florfenicol granule at 30 mg/kg. Comparative study on the pharmacokinetics of florfenicol powder and florfenicol granule was carried out. Plasma concentration of florfenicol was determined by HPLC. The concentration-time data of florfenicol were analyzed by non-compartmental model based on pharmacokinetic software WinNonlin 5.2.1. The main pharmacokinetic parameters of powder following oral administration were: t_1/2β=（10.22±0.18）h，k_e=（0.07±0.01）h^-1，t_max=（1.67±0.48）h，C_max=（24.68±1.13）μg·mL^-1，AUC=（190.97±16.60）μg·mL^-1·h，MRT=(8.33±0.42)h，t_cp=（17.66±1.52）h. The main pharmacokinetic parameters of granule following oral administration were : t_1/2β=（16.36±4.14）h，k_e=（0.05±0.01）h^-1，t_max=(5.71±0.47)h，C_max=(12.23±0.78)μg·mL^-1，AUC=（155.44±6.59）μg·mL^-1·h，MRT=(14.96±0.35 )h，t_cp=（23.03±0.49）h. The results showed the granule of florfenicol after oral administration had slower elimination and longer effective time of the blood medicine density maintenance.