The goal of this research is to investigate the corrosion inhibiting properties of a synthesized benzodiazepine derivative, 4-methyl-1,2-dihydro-3 H-benzo[b] [1,4] diazepin-3-one (MHBZO), in 0.5 M H2SO4 medium. Weight loss measures (WL), potentiodynamic polarization (PDP), and electrochemical impedance spectroscopy (EIS) were used to evaluate the effectiveness of the MHBZO molecule. The organic molecule exhibits an interesting and effective anti-corrosion properties, with a maximum inhibitory efficacy (IE%) of 93.07% at 10−3 M. According to the results of the PDP, MHBZO operates as a mixed-type inhibitor. The temperature influence demonstrates that MHBZO is chemisorbed on CS. As the isotherm appears to fit the Langmuir model, MHBZO is monolayer adsorbed on the CS surface. The growth of a barrier film restricting the accessibility of corrosive ions into the CS surface is revealed by scanning electron microscopy (SEM) and atomic force microscopy (AFM), resulting in a smooth protected surface. Theoretical investigations were carried out to back up the experimentally obtained results.