Solid lipid nanoparticles of cefixime were prepared by solvent- evaporation method using compritrol ATO 888 as the lipid core. The mean particle size of solid lipid nanoparticles, determined by Photon Correlation Spectroscopy (PCS), was 586.3 nm. The entrapment efficacy (EE) was measured using double beam UV/Vis spectrophotometry, reported 72.43. In vitro release was determined using USP apparatus type II (paddle type) in phosphate buffer saline pH 7.4. The drug release in the first 10 h was about 95.37 % of the total drug. In-vivo study was conducted on male rats after oral administration of cefixime solution and cefixime solid lipid nanoparticles in different formulations, the relative bioavailability of cefixime-SLNs was found to be 1.87. These results showed that cefixime absorption is enhanced by using solid lipid nanoparticles formulations.