A lubricating oil composition is disclosed which comprises a lubricating base oil, (A) at least one type of compound selected from specific phosphoric acid esters and salts thereof or in combination with (B) at least one type of compound selected from specific metal salts of specific phosphoric acid esters, with excellent oxidation stability, base number retention properties, anti-wear properties, extreme pressure properties and anti-corrosion properties and thus can be suitably used, in particular, as a lubricating oil for an internal combustion engine.