The inhibition actions of 1-phenylaminomethyl-benzimidazole（BMP）on the corrosion of N80 steel in HCl was studied by means of weight loss and electrochemical test. The results showed BMP could inhibit the corrosion of N80 steel in 5 mol/L HCl solution at the BMP concentration of 2 mmol/L, and the inhibition efficiency was more than 88% at the temperature of 333K. Active energies on the corrosion reaction increased with the increase of inhibitor concentration. The adsorption of BMP on the surface of N80 steel obeyed Langmuir isotherm, and adsorption energies were less than -35 kJ/mol in the temperature range of 303～333 K. In addition, the inhibition performance of BMP was investigated by molecular dynamics simulation method.