Abstract: This paper analyzes the on-chip transformer crosstalk effects between the layers, and the extraction of the on-chip transformer parameter and interconnection transmission lines modeling are studied. In order to reduce losses caused by the crosstalk effects, patterned shield structure which based on the principle of coplanar waveguide transmission lines shielding grid is proposed. Finally, the influence of patterned shield structure to on-chip transformer interlayer crosstalk is analyzed by the method of CO simulation. The results show that the shielding structure effectively decouples the interconnect lines of on-chip transformers.