Abstract: Continuous phase modulation(CPM) is widely used in digital communication systems due to its high spectral efficiency. According to the different modulation parameters, continuous phase modulation corresponds to a large class of modulation methods. A general CPM RF modulation system based on AD9364 RF transceiver chip was designed to solve the problems of complexity-implementation and poor portability. Firstly, the modulation design of baseband signal is completed according to CPM signal expression, including accumulated phase unit and related phase unit. Then, a series of conversion processes including interpolation filter and spectrum shift are completed through AD9364 direct up-conversion. Finally, test result shows that the CPM RF modulation system has high spectrum utilization, low complexity and good generality.