A method to reduce crosstalk using TL-shaped defect microstrip structure (DMS) is proposed to solve the far-end crosstalk between microstrip lines. This method optimizes the ratio of the capacitive coupling and the inductive coupling between the coupled microstrip lines by etching the TL-shaped DMS on the microstrip line and reduces the strength of the electromagnetic (EM) coupling, which can achieve crosstalk suppression. The equivalent circuit model, S-parameters and full-wave EM simulations are used to analyze the crosstalk between the microstrip lines etched with and without the TL-shaped DMS. High Frequency Structure Simulator (HFSS) software simulation and samples test results show that the TL-shaped DMS can effectively reduce the far-end crosstalk while guaranteeing the transmission ability of microstrip line to the signal. The maximum far-end crosstalk can be reduced by 42dB in the frequency range of 0–8 GHz and the test results of the samples are in good agreement with the simulation results.