Anew simple, convenient and suitable spectrophotometric method for simultaneous determination of Furosemide and Spironolactone in combined dosage form has been developed and validated. Simultaneous equation method (Vierordt’s method) was used for determination of Furosemide and Spironolactone in combined dosage form. For spectrophotometric method development double distilled water and ethanol were used as a solvent in the ratio of (20:80). The proposed method was quantitatively evaluated in terms of linearity, precision, accuracy, lower limit of detection (LOD) and quantification (LOQ), recovery and robustness. All the parameters were found to be within the acceptance limit. λmax of Furosemide and Spironolactone was found to be 275 and 237 nm respectively. Beer’s law was obeyed over the concentration ranges of 2-10 μg mL−1 for both Furosemide and Spironolactone respectively. The % assay for commercial formulation was found to be 99.60%±0.0500 for Furosemide and 100.26%±1.17 for Spironolactone by the proposed methods. The overall recovery was observed to be 100.38±0.09% for Furosemide and 100.49±0.4197% for Spironolactone by simultaneous equation method (Vierordt’s method). LOD and LOQ were 0.76 and 2.32 μg mL−1 for Furosemide, 1.99 and 6.04 μg mL−1 for Spironolactone. A new simple, convenient, precise, rapid, accurate and economical and reliable spectrophotometric method was developed and validated for the analysis of Furosemide and Spironolactone in bulk drug and their formulations.