IN THIS RESEARCH, TOW NEW LEAD ION SELECTIVE MEMBRANEPOTENTIOMETRIC SENSORS BASED ON BENZO-18-CROWN-6 AS NEUTRAL CARRIER IN POLY VINYL CHLORIDE[1] (PVC) MATRIX WAS FABRICATED BY TWO IMMOBILIZED LIQUID MEMBRANE AND COATED GRAPHITE FORMS. THE ELECTRODES SHOWS A LINEAR DYNAMIC RESPONSE IN THE CONCENTRATION RANGE OF 1.0´10-3-1.0´10-7M WITH A NERNSTIAN SLOPE OF 28.2±0.5 AND 30.0±0.5 MV PER DECADE AND A DETECTION LIMIT OF 1.6´10-7 M FOR IMMOBILIZED LIQUID MEMBRANE ELECTRODE AND1.1´10-7M FOR GRAPHIT COATED ELECTRODE. THE ELECTRODES SHOW A GOOD REPRODUCIBILITY AND HAVE A GOOD RESPONSE TIME OF 15 AND 5 S AND A LIFE TIME OF 9 AND 15 DAYS FOR IMMOBILIZED LIQUID MEMBRANE AND GRAPHIT COATED ELECTRODE RESPECTIVELY. THE BEST PERFORMANCE WAS OBTAINED WITH A MEMBRANE COMPOSITION OF 26.6% PVC, 68% DOP, 4.1% BENZO 18 CROWN-6 AND 0.91% SODIUM TETRAPHENYLBORATE FOR LIQUID MEMBRANE AND A MEMBRANE COMPOSITION OF 27% PVC, 70% DOP AND 2.7% BENZO 18-CROWN-6 AND 0.1% SODIUM TETRAPHENYLBORATE FOR GRAPHIT COATED ELECTROD. THE POTENTIOMETRIC RESPONSE OF THE PROPOSED ELECTRODES IS INDEPENDENT OF THE PH OF SOLUTION IN THE RANGE OF 3> PH >12 AND 4>PH >12 FOR LIQUID MEMBRANE AND COATED ELECTRODE RESPECTIVELY. THE BOTH OF ELECTRODE SHOWS GOOD SELECTIVITY (BASED ON MATCH POTENTIAL METHOD [2, 3]) TOWARDS LEAD AGAINST MOST OF THE TRANSITION AND COMMON ALKALI, ALKALINE EARTH METAL.