A new selective and sensitive Tb3+-PVC membrane sensor was developed using an ion carrier named 1,4-bis[o-(furan-2-carboxamidophenyl)]-1,4-dithiobutane (FCT). The sensor has a linear dynamic range between 1.0×10-7-1.0×10-2 M, with a near Nernstian slope of 20.7 ± 0.2 mV per decade, a detection limit of 7.5×10-8 M with a membrane composition of 30% poly(vinyl chloride), 66% dibutyl phthalate (DBP), 2% sodium tetraphenyl borate and 2% FCT. The potentiometric response of the proposed electrode is pH independent in the range of 2.5–7.8. The response time was relatively quick in the whole concentration range (~ 5 s). To investigate the membrane sensor selectivity, its potential response was determined in the presence of various interfering foreign cations using the matched potential method. This sensor demonstrated good selectivity and sensitivity towards the terbium ion for a broad variety of cations, including alkali, alkaline earth, transition and heavy metal ions. The developed sensor was successfully applied as an indicator electrode in the Tb(III) ion potentiometric titration with EDTA.