A new, efficient Calcium ion selective electrode has been prepared using Surface modified Zeolite based ionophore.The prepared ionophore is characterized by UV,FT-IR,XRD..The sensor exhibits a near Nernstian response for Ca(II) ion over a concentration range of 1.0 X 10 -4 M to1.0 M . The proposed sensors revealed relatively good selectivity and high sensitivity for Ca(II) over a monovalent cations. It can be used with in the pH range of 5.57 to 6.24 . The effect of medium and the selectivity coefficient values was evaluated using fixed interference method found to give a better response. . It was also successfully used in the analysis of concentration of Calcium ion in various real samples.