Abstract: Both brassinosteroid and IAA promoted rice laminae inclination and were inhibited by TIBA, but rice laminae were much more sensitive to brassinosteroid than to IAA.The effect of rice laminae inclination caused by 0.01m mol/L BS was three times as much as that by 100m mol/L IAA; both effects were inhibited by 100m mol/L TIBA.Additionally,brassinosteroid and IAA had a synergistic effect on the action of rice laminae inclination.