The electrostatic boundary-value problem of a dielectric-wedge-backed, slotted conducting wedge is solved to analyze an asymmetric coplanar striplines (ACPS) by using the Mellin transform and a mode-matching method. Numerical computations are performed to assess the characteristics of the ACPS in terms of the strip geometry and relative permittivity of a dielectric substrate. In order to check the validity of our theoretical approach, the computed results are compared with the simulation results as well as the results by the conformal mapping.