This work was initiated by QFB Alejandra Jimenez Diaz with the interest of making a compilation of the main tests that are performed in a clinical laboratory, as part of her thesis work under the direction of M. en C. Ma del Socorro Martinez. This project describes some basic areas of a laboratory, as well as routine studies that are performed on patients who come to request clinical service. These activities of the Laboratory are proper of the Pharmaceutical Chemist Biologist to report the results of the analyses performed that are of valuable utility for the prevention, diagnosis, support to the treatment and follow-up of diseases.