A PVC membrane sensor for dysprosium(III) ions based on N,N’-bis(naphthalidene)-2- aminobenzylamine (BNA) as a suitable ionophore with a linear dynamic range of 1.0 × 10-6-1.0 × 10-2 M, a Nernstian slope of 20.7 ± 0.4 mV per decade, a detection limit of 5.2 × 10-7 M, pH range of 2.5–8.6 and response time of ~7 s was constructed. In this research, on the fabricated electrode, the potential responses of the recommended Dy(III) membrane sensor to a wide variety of cations were investigated through the matched potential method (MPM). The recommended sensor revealed comparatively good selectivity with respect to most alkali, alkaline earth, some transition, and heavy metal ions. It was successfully employed as an indicator electrode in the potentiometric titration of Dy(III) ions with EDTA.