Herein, we developed a novel potentiometric sensor that exhibits high selectivity towards Ag+ ions, using a newly synthesized phenol derivative (4) molecule as an electroactive material (ionophore). The sensor was prepared by coating the surface of a conductive solid contact by a membrane containing bis(2-ethylhexyl)sebacate (BEHS) as plasticizer, poly (vinly chloride) (PVC) as a polymeric matrix, electroactive material (4), and potassium tetrakis(4-chlorophenyl)borate (KTpClPB) as an additive. The developed sensor exhibited a wide linear concentration range of 1.0x 10(-6)-1.0x 10(-1) mol L-1 and a lower detection limit of 5.87 x 10(-7) mol L-1. The sensor exhibited quite good selectivity over other cationic species, and its potential response remained unaffected of pH in the range of 3.0-7.0. In addition, the developed sensor had a short response time of 8 s, good repeatability, and stability. Finally, the proposed sensor was used in the direct determination of Ag(+ )in different water samples, and as an indicator electrode for the end point determination in the potentiometric titration of Ag+ ions against sodium chloride.