International audienceIn this work, an asymmetrical microstrip SPICE model for crosstalk evolution used in telecommunication sectors is presented. In a first part, we evaluate the per unit length parameters in coupled microstrip lines by mathematical model based on the method of moments. In a second part, predicting near-crosstalk and far-crosstalk are realized by a SPICE model. The model allows the study of the crosstalk evolution in function of physical parameters, and the electrical signal dynamic. Some curves are proposed in function of strip width, spacing, and electrical stress, which can help the designer in the conception for limiting the adverse effects of crosstalk