With the in-depth research on the Microwave Photonic Filter（MPF）

the design methods and MPF performances have been enormously improved

but little reports about the development of some typical filters with given parameters have been made.On the basis of the in-depth research on the digital filters and MPF structures

the detailed design process of the bandpass Butterworth MPF using the design method for digital filters is given

obtaining the zeroes and poles of the required transfer functions.The filter transfer functions are implemented by using fiber ring-assisted cascading Mach-Zehnder Interferometer（MZI） cascading and the structural parameters of various cascaded MZI such as coupling coefficients

arm length differences and the ring length are determined by the calculation of the zeros and poles of the transfer function.They are verified in simulation and the results are basically in agreement with the design requirements.Furthermore

the effects of different structural parameters on MPF are investigated.