trace determination of INDP inpresence Cu [II] , due to the strong adsorption of the Cu [II] - INDP complex at the surface of the HMDE andsubsequent reduction of the surface - bound complex. The observed data has been subjected to statistical analysis, which revealed high reliability and precision. A detection and quantitation limits of 2.9x10 [-11] and 8.8x10 [-11] mol/L [-1] respectively, were achieved in presence of 5.0x10 [-7] mol/L [-1] Cu [II] . The proposed procedure is much simple, fast, more sensitive, reproducible and the calibration graph is linear over range 2.0x10 [-12] -2.0x10 [-7] mol/L [-1] . Moreover, this method was successfully applied to the direct determination of INDP in pharmaceuticals and spikedhuman urine. No prior extraction step is needed in case of urine. The effect of some interferences [Mg [+2] , glycine, Fe [+3] , uric acid, starch, glucose and Na [2] CO [3] was considered