In this work, the standard procedures required for the operation, verification and maintenance of a liquid chromatography coupled to mass spectrometry system have been developed. These procedures have been designed and prepared with the aim to establish a quality control system to ensure the proper functioning of each component of the instrumentation, the LC and the MS, and to verify the performance of the LC-MS coupling. For this purpose, standard procedures were elaborated and proved in the normal routine laboratory work to evaluate their real applicability. Moreover, the verification of the performance of the LC-MS system was carried out experimentally through an in-house procedure based on the analysis of naphthylacetics