To develop a new product pharmaceutical industries, use analytical methods to quantify the active principle fast and reliable. The validation was determined if the method is reliable and reproducible, for this reason the present work validated an analytical method by high resolution liquid chromatography to quantify sennosides in chocolate bars, the type of research was descriptive with simple random sampling. The chromatographic conditions at 274 nm, mobile phase with a flow gradient ranging from 0.4 to 1, 5 mL / minute and solvent, composed to phosphate buffer pH 3.5 and Acetonitrile, injection volume 40 μL. The evaluated validation parameters confirmed specificity, linearity to concentrations of 0.07; 0.11; 0.15; 0.19 and 0.23 mg / mL with a correlation coefficient of 0.9996, precision with a coefficient of variation less than 2 %, accuracy of 98.6 % and robustness after 24 hours wit...