The results of a study on the feeding habits of L. olivacea and C. mydas agassizi from the Pacific coast, located at 19ºN and 105ºW, are presented. A preference for feeding on crustacea was observed on L. olivacea, proving to be essentially a carnivorous specie. In the case of C. m. agassizi a certain balance between algae and animal feeding was appreciated, beeing the plants in a greater volume and animals more diversified. Related to animal preying C m. agassizi bucal structure, seems to be adapted toward the retention of animals captured with algae. Apparently there is no competition for food between both species,, given that L. olivacea feeds on organisms from sandy bottoms, while C. m, agassizi feeds on arrecifal or rocky bottoms.