The present study narrates the developed and validated simple, reliable, sensitive, precise and accurate Spectrophotometric and RP-HPLC methods for the simultaneous estimation of Fenbendazole and Niclosamide in pharmaceutical dosage form. In the first order derivative method 0.1 N methanolic HCl was used as diluent. The zero crossing point wavelengths selected for the analysis were 226 nm and 317 nm for Fenbendazole and Niclosamide, respectively and RP – HPLC method has been developed using 1% methanolic HCl as diluent. Separations of drugs were achieved on L1 C18 100 A0 column (250 x 4.6 mm, 5 μ) using 2 gm potassium dihydrogen phosphate and acetonitrile (70:30, v/v) as mobile phase with flow rate 1.0 mL/min. The detection wavelength was 290 nm. Validation of developed methods was done according to ICH Q2 (R1) guideline. Calibration curve was linear over the concentration range of 3-9μg/mL (Fenbendazole) and 10-30 μg/mL (Niclosamide) for spectrophotometric method and 24 - 39 μg/mL (Fenbendazole) and 80 – 130 μg/mL (Niclosamide) for RP – HPLC method. The developed RP-HPLC and derivative spectrophotometric method were successfully applied for the quantitative determination of cited drugs in pharmaceutical dosage form. The correlation coefficients (r2) value greater than 0.995. Accuracy of methods were determined by recovery studies and it was found to be 98 to 102 %. The % RSD values for all the validation parameters were less than 2.0 % for both the methods. The developed UV and RP-HPLC methods were compared by t - test and it was found that tstat value was less than tcritical value for all. Hence there was no significant difference between the developed methods.