Thepartialchargesimulationmethodispresentedtosolvethecharacteristicimpedanceofthetransmissionlineofspecificcrosssectionwithanoffsetinnerconductor.Thismethodhasahigheraccuracyduetotheaccuratesatisfactionoftheboundaryconditionontheouterconductor.ThecombinedmethodoftheGausseliminationandoptimizationisusedtosolvetheequationofchargesimulation,anditisaneffectivemethodforincreasingtheaccuracyandassuringtheconvergence.TheGreen’sfunctionsoffivetransmissionlines(i.e,withcircular,elliptic,rectangular,troughandslabconductor)aregiven.