A simple and direct spectrodensitometric method has been developed for the qualitative and quantitative determination of three pairs of diuretic mixtures: i- spironolactone with hydrochlorothiazide, ii- captopril with hydrochlorothiazide and ii- spironolactone with furosemide p-Chloroacetanilide was used as internal standard in quantitative determination. The method was applied for the determination of these drugs in different pharmaceutical dosage forms: Aldactazide, Capozide tablets and Fructone capsules. The results indicated high accuracy and reproducibility.