The influence of (0.95-x) Bi2O3-x B2O3-0.05 (Ta2O5-Nb2O5) named A1 on the corrosion of steel in 1M HCl was investigated. Electrochemical polarization and impedance spectroscopic studies measurements were used. The inhibition efficiency increases with A1 content to reach 88% at 150 ppm. Polarisation curves show that A1 acts as a cathodic inhibitor. The increase in temperature leads to an decrease in the inhibition efficiency of the A1 inhibitor. The activation energies in the presence and absence of inhibitor have been determined and discussed.