A novel ultra wideband(UWB) filter with the center loaded folded multiple mode resonator structure is designed to improve the problem of large insertion loss and bad rejection features outside of the pass band.Different resonance frequency of the resonator can be adjusted by changing different parameters of the multi mode resonator structure of the filter.The filter has better performance with some merits, such as compact structure,small size,low insertion loss and better rejection features outside of the pass band,and so on. Simulation results show that the pass band of the filter is from 3 GHz to 10.7 GHz at 6.85 GHz center frequency,achieving 112% relative bandwidth. The tests results are approximately conform to the simulation results.