A highly efficient and environmentally benign electrode has been developed for the easy and fast detection of hydrazine by modifying a gold electrode with polyglycine. The polymerization of glycine on a Au electrode was carried out by cyclic voltammetry. A detailed investigation of the oxidation of hydrazine on the electrode was carried out by cyclic voltammetry (CV), chronocoulometry (CC) and amperometry in 0.02 M phosphate buffer (PBS), pH 7.4 as supporting electrolyte with Ag/AgCl as reference electrode. A very low detection limit (16 nM) (S/N = 5) and a good linearity in current with high sensitivity (1.2 μA μM⁻¹ cm⁻²) over a concentration range of 16 nM to 259 μM was achieved by the amperometry technique. The electrode shows good selectivity in presence of many other species and is stable for nearly ten repetitive experiments.