In this work, 1-benzyl-4-ferrocenyl-1H-[1,2,3]-triazole (BFT) and carbon nanotubes has been applied to construct a modified glassy carbon electrode. This modified electrode showed electrocatalytic activity for oxidation of hydrochlorothiazide (HCT) and reduced the overpotential for oxidation of hydrochlorothiazide about 870 mV. Also, the modified electrode can resolve the overlapped voltammetric peaks of hydrochlorothiazide and propranolo into two voltammetric peaks. This property allows to selective determination of hydrochlorothiazide in the presence of propranolol. The transfer coefficient (α) and diffusion coefficient of hydrochlorotjiazide were also investigated. In phosphate buffer solution (PBS) of pH 8.0, the oxidation currents for hydrochlorothiazide increased linearly from 0.1 to 500.0 μM using square wave voltammetry (SWV). The detection limit (3σ) was obtained 0.08 μM. The proposed method was successfully applied to the determination of hydrochlorothiazide and propranolol in pharmaceutical and biological samples.