Abstract: Base on the assumption that disturbance to a critical pin is mainly caused by the nearest surrounding pins, a model of crosstalk in connector is given, the validity of the model is discussed. Method of moment is used in the determination of per-unit-length parameters. Harmonic series expansion functions are selected which converge more rapidly than delta function expansion and simplified the simulation. Extreme terminal conditions of connector are studied, results are given in frequency domain coupling factors and time domain waveforms, simulation results may be helpful for the usage of connector correctly.