. Tetracycline sorbed zirconium(IV) tungstophosphate (TC-ZWP) has been used as a chelating agent for determination of rare earth metal ion i.e Nd(III). The poly(vinyl-chloride)-based membrane electrode exhibits a Nernstian response for Nd(III) ions over a wide concentration range (1 x 10(-1) to 5 x 10(-1) M) with detection limit of 5 x 10(-5) M. It has 25 s response time and can be used upto 45 days without any divergence in its potentials. The proposed membrane sensor reveals good selectivity for Nd(III) ions within the pH range of 3-7. Analytical application of electrode has been investigated for the quantitative determination of Nd(III) in sibaiya phosphate ores. It has been also successfully used as an indicator electrode in the potentiometric titration of Nd(III) against standard EDTA solution.