Biodiesel is one of the alternative sources of energy obtained from the edible oils used in different types of kitchens as a renewable resource. The by-product derived from the reaction process transesterification in the production of biodiesel is glycerin the aqueous glycerin solution is filtered to remove the impurities and then neutralized with 1N NaOH. The objective of this work was to identify the characteristics of this glycerin and its applications and future use, the characterization made of this by-product from which it was collected. liters in amber bottles, the pH range between 6 and 7, density 1.24 g / l, viscosity .897 pascal sec., it is possible to recover methanol to a purity of 58% by weight, glycerin is used in many products of consumption, has a low toxicity, its properties are stability and compatibility towards other chemical compounds. The applications of this by-product are the manufacture of liquid soap, degreaser, floor cleaning, it is a non-irritating, biodegradable and recyclable compound.