This article reports the theoretical and experimental study of nonresonant mechanisms (CHEM) of surface‐enhanced Raman spectroscopy (SERS) of pyridine (Py). An improvement in the Raman dispersion intensity of Py is determined after the chemical absorption on CuO nanoparticles synthesized in NaCl. The density functional theory predicts the formation of new electronic states as result of the chemical bond (CB) established between the Py molecule and the (CuO)n clusters. This study is focused on the study of the most intense vibrational modes of Py before and after chemical adsorption. The CHEM by CB mechanisms is found as responsible for the SERS effect in Py.