A simple, selective, and sensitive HPTLC method for the determination of Dicloxacillin in Simulated Urine was developed & Validated. The method utilizes Protein precipitation as the sample preparation technique. The HPTLC separation was achieved on the aluminum backed layer of silica gel 60 F254 using Toluene : methanol : Triethylamine (4:6:0.5% v/v/v) as mobile phase. The Detection wavelength used was 227nm. The chamber saturation time is 15min.Cefixime was used as an internal standard. The calibration curve was linear ( r2>0.99) through the range of 200-1000ng/band. The mean recovery was found to be 93.31% for Dicloxacillin. Quantification was achieved with HPTLC, over the concentration range of 200 to 1000 ng/band. Retention factor (Rf) for Dicloxacillin and Cefixime (IS) were 0.80 and 0.50 respectively. Dicloxacillin was found to be stable in simulated urine. The method showed acceptable values for accuracy, precision, recovery and stability.