The oxidation of glycerol into lactic acid using 1 wt% Au/bentonite as heterogeneous catalyst was studied. Several reaction parameters were evaluated: catalyst reduction, oxygen presence, catalyst amount, hydroxide type and NaOH/glycerol molar ratio and reaction time. The textural and structural properties of the bentonite supported Au catalysts were evaluated by XRD, SEM and ICP. The reactions were performed in a 100 mL volume three-necked and round-bottomed flask placed in an oil bath at 90 degrees C reaction temperature and atmospheric pressure. It was possible to achieve a glycerol conversion of about 82.4% with selectivity to lactic acid of 92.3% and 76.1% yield, at 90 degrees C of reaction temperature, NaOH/glycerol = 8 mol ratio by using 0.25 g catalyst after 240 min reaction.