The effect of various heterocyclic compounds containing nitrogen, oxygen, sulfur, or selenium atoms on the corrosion of type 304SS in 2M sulfuric acid solution was studied by weight loss, gasometry, de and ac techniques. It was found that the inhibition efficiency of tested compounds follows the order 2-methylbenzoselenazole (2-MBS) > 2-methyl-benzothiazole (2-MBT) > 2-methylbenzoxazole (2-MBO) > 2-methylbenzimidazole (2-MBI); the adsorption isotherms follow the Frumkin isotherm and the thermodynamic/kinetic model. Polarization curves showed that these compounds acted by decreasing the available surface area with no change in reaction mechanism. The stability of the formed film was verified by the AC impedance technique.