The florfenicol(FF) - Polyethyleneglycol 6000 (PEG6000) solid dispersions (SDs) were prepared by melting and solvent-melting method with PEG6000 as carriers. The SDs were validated by infrared spectroscopy, microscopy, differential thermal analysis and dissolution rate. The solubilities of FF, mixture and SDs were measured. The spectrophotometer method was developed to determine the concent of FF. It was found that the spectra of infraed spectroscopy, differential thermal analysis of the SDs were remarkably different from that of FF and physical mixture. Solubility of FF was 1.118 mg/mL for the formation of SDs. The average recoveries of FF were 100.5% and relative standard deviation was less than 1.0%. The calibration curve was linear with an correlation coefficient r = 0.999 8 in range of 50.0~350.0 µg/mL. The method was simple in preparation, validation and determination the FF/PEG6000 SDs. Solubility of FF was enhanced remarkably for the formation of SDs.