In the structure of inverted Microstrip with complementary split-ring resonator, a new type of compact bandpass filter is designed. Nematic Liquid Crystal is introduced in this structure. Through changing the applied voltage, the properties of liquid Crystal are also changed , and it is easy to adjust the center frequency of the bandpass filter. Arbitrary frequency bandpass filter is easier to be achieved by means of this feature. The bandpass filter has the advantage of compact size, low loss, easy fabrication and easy integration with other circuits. Using this feature can be easier to achieve perfect microwave bandpass filter.