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To study the residue management effects on grain yield and its components in a continuos winter wheat cropping system undor irrigation a five - years experiment (1993-1998) was conducted at the agricltural research station of Shiraz. University, located at Koushkak. The treatments were composed of: a) sowing after residue burning, removing, plowing or disking and b) sowing wheat in residue with chisel seeder when the straw was left erect, the land was first irrigated and then sown with or without herbicide application. The results indicated that the highest grain yield was achieved when the residues were either removed or burnt. Such greater grain yield was the result of increased grain number per unit area with no significant change in mean kernel weight. Increased grain number per unit area with no significant change in mean kernel weight. Increased grain number per unit area was due to both increased number of fertile shoots per unit area and number of grains per ear. Greater fertile shoots per unit area in burning or removing straw treatments was associated with better plant establishment and enhanced tillering. It was observed that only small amounts of the residue left could be decomposed during the period between thd harvest of previous crop and next sowing time due to low soil moisture content. Continuous residue accumlation, resulted in poor estabilishment of the crop, reduced plant denstity and lower yield, under the conditions of this experiment. It is therefore recommended to remove all the wheath straw before the seed bed prepatation under similar conditions.