Abstract: The asymmetric coplanar waveguide bend was studied for decreasing the insertion loss of coplanar waveguide bend through numerical algorithms and experiments.Combining multiresolution time domain(MRTD) algorithm and the method of extracting characteristic impedance from Y parameters, a formula for decomposing the signal on asymmetric coplanar waveguide into c and π modes was derived.The transmission coefficients of the asymmetric coplanar waveguide bend were calculated.Based on the theoretical analysis, a new test fixing was proposed for measuring the mode conversion through vector network analyzer.The theory and experiment results show that compared with coplanar waveguide bend, the asymmetric coplanar waveguide bend has low mode conversion and low insertion loss.