Abstract: The kinetic behaviors of schlögl's model A+2X<=>3X and X<=>B has been studied under the continuous flow stirred reaetor(CSTR)conditions. The parameters' regions, in which the reaction system exhibits all kinds of different kinetic behaviors e.g. bistability and limit cycle oscillation, can be divided by the phase plane method. The system may exhibit oscillation or bistability for some range of flow rates under the constraints of all other parameters being fixed. This method, with advantages of simplicity in calculation and explicitness in physical background, offers an effective path for designing chemical oscillation and predicting other kinetic phenomena.