Abstract: Problems such as drug abusiveness, poor efficacy, nonquantitatively medicine and improper administration raised high morbidity and mortality in Pseudosciaena crocea fishery. A biodegradable antibiotic pill was manufactured, in which starch, chitosan and gelatin were used as carriers and florfenicol, a broad spectrum antibiotic in fishery, was used as the model drug. The carrier's morphology, water uptake, bacteriostasis capability and drug-residue of the pill were analyzed using scanning electron microscopy (SEM), high performance liquid chromatography (HPLC), in vitro and in vivo test. The microscopic structures of both carrier and pill were quite uniform in pore size and pore distribution with good interconnectivity between pores, which is favorable for the drug's circulation and release. The in vitro bacteriostasis test showed that the pills were effective against Vibrio alginolyticus while the carrier materials were little antimicrobial active. The in vivo toxicity, pharmacokinetics and drug residues as a function of time were tested with Pseudosciaena crocea as the test fish. The blood, liver and muscle of tested fishes were obtained and evaluated. The results showed that the carrier materials were low toxic for Pseudosciaena crocea.5-7 days after oral administration, trace level residue of florfenicol was tested in blood, liver and muscle tissue of Pseudosciaena crocea. The pharmacokinetics was in line with a two-compartment open model with first-order absorption factor.