The effect of hydrochloric acid and sodium hydroxide solutions on some lead borate glasses containing high proportions of lead oxide was investigated to study the chemical durability of these glasses in different aqueous media. Different factors were studied such as the glass compo¬sition, concentration of the aqueous solution, temperature and time of immersion. The change in the value of the mass loss (S in g cm'2) with the change in the glass composition was found to be due to the change in the corrosion rate. In the case of increasing the concentration of the immersion solution, the increase in the mass loss can be attributed to the pH value. The results obtained from the immersion condition were also explained.