A simple, economical, precise and accurate method for simultaneous determination of Diclofenac potassium (DICLO K) and Thiocholchiside (THIO) in combined dosage form has been developed. The first method is based on Ratio Derivative (Method A) and second method is based on Dual Wavelength (Method B). The amplitudes 268.78 nm and 355.62 nm wavelength were selected to determine THIO and DICLO K respectively, by method A. In method B, two wavelengths were selected for each drug in a way so that the difference in absorbance is zero for another drug. At wavelengths 252.47 nm and 260.74 nm Thiocholchiside have equal absorbance therefore these two wavelengths were used to determine DICLO K and on similar basis 263.22 nm and 301.65 nm were selected to determine THIO in combined formulation. The drugs obey Beer?s law in the concentration range of 12.5-75 __ampersandsignmu;g mL-1 for DICLO K and 2-12__ampersandsignmu;g mL- 1 for THIO by the method A and 25-75 __ampersandsignmu;g mL-1 for DICLO K and 4-12 __ampersandsignmu;g mL-1 for THIO by the method B. The % assay of DICLO K and THIO was found to be in the range 99.95 __ampersandsignndash; 100.29 % by the proposed methods. Recovery was found in the range of 98.6 - 101.0 % for both analytes by both methods. The results of analysis have been validated statistically and recovery studies confirmed the accuracy and reproducibility of the proposed methods which were carried out by following ICH guidelines.