This study aimed to evaluate the physical and chemical quality of tablets Naproxen Sodium 550 mg sold on the domestic market Through his physico-chemical parameters such as description, loss on drying, breaking strength, average weight and disintegration. For it was based on the development of the analytical technique in process of a national laboratory identified with internal code (CC.EMPP-P.15) and compliance with the technical specification of the finished product Naproxen sodium 550 mg coated tablets internal code (CC.EMPT-P.15); which is itself based on the official monograph USP 38. After the analysis performed physicochemical quality concluded that lots A and B meet the specifications of description, loss on drying, breaking strength, average weight and disintegration, established in USP 38