Abstract: Applying the theory of CISK to a two-level model,the effects of environment temperature gradient on the development and movement of tropical disturbances were analysed.The results are as follows:The gradient has a notable influence on the development of disturbance,and is related with both the direction of the gradient and the relative position between the gradient and the disturbance.Also,the gradient makes the disturbance move toward the warm air area.The above results may give some dynamic explanation to the effects of the cold air on the development and movement of typhoon and throw light on the mechanism of the developing of convective systems under baroclinic conditions and the parameterization of these systems.