 The study found that 2TP is an effective corrosion inhibitor for mild steel in 1.0 mHCl solution, with an inhibition efficiency of 94.6%. The inhibition efficiency increased with an increase in concentration of 2TP and decreased with an increase in temperature. The adsorption of 2TP on the mild steel surface was mainly through the interaction of the lone pair of electrons on the nitrogen atom of the thiodiazol ring with the metal surface. The results obtained from weight loss, potential dynamic polarization, electrochemical impedance spectroscopy, EIS, and open circuit potential, OCP, measurements were in good agreement with each other and confirmed the effectiveness of 2TP as a corrosion inhibitor in acidic environments. This article was authored by Ahmed Alemiy, WAN, nor Rosland WAN Isaac and Walid Khalid Al-Azawi.