A dual-port anti-corrosion method for complex permittivity measurement with transformation of coplanar microstrip structure is presented，including a Coplanar Waveguide(CPW) based measurement device and an inversion algorithm trained with artificial neural network algorithm. Compared with the traditional methods，this method has better sensitivity，more simple structure，dual-port mode and other advantages. Furthermore，the device does not have any direct contact with solution in measurement， therefore it has excellent corrosion resistance, and can be widely used in corrosive solution permittivity measurements. This method is employed to measure the complex permittivity of methanol-water solution and ethanol-methanol solution with various concentrations at 2.45 GHz. The measurement results of the permittivity of solutions agree well with the theoretical values.