A new PVC membrane electrode for zinc ions based on a recently synthesized benzo-substituted macrocyclic diamide (1,13-diaza-2,3;11,12;15,18-tribenzo-4,7,10-trioxacyclononaoctane-14,19-dion e) as membrane carrier was prepared. The sensor exhibits a Nernstian response for Zn 2 + over a wide concentration range (1.0x10 - 1 -9.0x10 - 5 M). It has a response time of about 20 s and can be used for at least 3 months without any divergence. The proposed membrane sensor revealed good selectivities for Zn 2 + over a wide variety of other metal ions and could be used in a pH range of 3.0-7.0. It was successfully used for direct determination of Zn 2 + in solution and, as an indicator electrode, in potentiometric titration of zinc ions.