Volatile components in extruded maize flour at 140℃were extracted by SPME,identified and evaluated by GC-MS.More than 90 compounds were successfully detected.Among the flavor active volatiles,pyrazines were the most prominent class of compounds,especially the alkyl substituted derivatives,followed by furans.Few pyrroles and sulfur-compounds were also identified.The above classes are highly contributed to the overall flavor,in spite of their relatively low amounts which is due to the low extrusion temperature.