A new electrochemical sensor has been constructed based on the in situ preparation of gold nanoparticle embedded on reduced graphene oxide and polypyrrole nanotube (AuNP@rGO/PPyNT) composite through a nanosecond laser-induced heating technique. The as-prepared composite is used for individual as well as the simultaneous electrochemical determination of chemotherapy drug (furazolidone, FU) and anticancer drug (flutamide, FLT). The composite was analyzed by X-ray Diffraction, scanning electron microscopy/energy-dispersive X-ray analysis, transmission electron microscopy, Raman spectrometry, and X-ray photoelectron spectroscopy analysis, thus confirming the successful synthesis of this composite and its physical features. The modified AuNP@rGO/PPyNT electrode was examined through cyclic voltammetry and differential pulse voltammetry (DPV) methods in pH 7.0 for the determination of FU and FLT in individual, simultaneous, and mixed systems. The fabricated sensor showed wide linear responses (0.01-1080.11 μM and 0.01-1214.11 μM) of analytes, with the lower limits of detection of 2.3 and 2.45 nM and higher sensitivity of 53.75 and 50.06 μA μM-1 cm-2, respectively. Furthermore, the constructed sensor demonstrates higher stability, reproducibility, and repeatability, and is effectively applied for the analysis of FU and FLT content in the human serum sample analysis with satisfactory recovery.