The effect of the container surface on the thermal degradation of vegetable oil was investigated. Coconut, canola, soybean, sunflower, groundnut and rice bran oils were heated in glass, copper and iron containers of identical shape, size and thickness. Peroxide value, p-anisidine value, totox value, total polar contain, free fatty acid value, saponification value, iodine value, antioxidant and metal contains were evaluated before and after heating. The results showed that the container surface had a tangible effect on thermal degradation. Metal surfaces are generally more pro-oxidizing with iron being more active than copper. Only sunflower oil showed maximum oxidation in copper. Re-esterification is promoted in copper surfaces. Container surface also affects the change in iodine value. Copper ions leach from the container into the oil in most of oil types. The metal surface also accelerates the degradation of antioxidants in the oil. Iron is the most efficient in this regard.