Heavy quark systems (c and b ) have been studied in the nonrelativistic framework using energy dependent interquark potential of the form harmonic oscillator with a small linear term as energy dependent as perturbation plus a inverse square potential. This potential admits exact analytical solution of the Schrodinger equation. Mass spectra, leptonic decay width, root mean square radii (), the expectation value of the radius (r) and have been estimated for different quantum mechanical states for and systems. It is observed that energy dependent term in the potential leads to saturation of the mass spectra and degree of saturation is governed by the magnitude of perturbation. The calculated values of leptonic decay widths for 1s state are in very good agreement with the experimental data both for c and b systems.