Siberian fir oil, also known as Abies sibirica, is used as a dispersion medium for suspensions containing titanium oxide and zinc oxide nanoparticles. Corrosion tests were conducted on bronze and St3 (S235JR) steel samples using accelerated tests in a solution of concentrated acids, including optical microscopy, gravimetric analysis, and X-ray diffraction. Additionally, dilute acid solutions were used for Tafel diagram analysis and impedance spectroscopy. Based on the results of the corrosion studies, it was determined that fir oil significantly improves the corrosion protection of St3 steel in a 0.1 M HCl solution by 74.2%. The addition of zinc oxide nanoparticles further enhances this protection to 90.4%. For bronze, fir oil alone provides a corrosion protection of 47.9% in a 0.1 M H2SO4 solution, while the addition of titanium oxide nanoparticles increases this protection to an impressive 98.6%.