An anticancer drug, dasatinib (DAS), is used to treat prostate cancer, chronic myelogenous leukaemia, and acute lymphoblastic leukaemia. In the present work, we describe the preparation of zinc oxide (ZnO) nanoparticles (NPs) using Averrhoa bilimbi leaf extract. These ZnO NPs were combined with functionalized multi-walled carbon nanotubes (f-MWCNT) to prepare a ZnO@f-MWCNT nanocomposite for electrochemical sensing of DAS. The prepared electrode materials, ZnO NPs, f-MWCNT, and ZnO@f-MWCNT, were characterised by powder X-ray diffraction (XRD), scanning electron microscopy (SEM), the Fourier-transform infrared (FT-IR) spectrum, atomic force microscopy (AFM), zeta potential, and the dynamic light scattering (DLS) techniques. DAS exhibited a significant enhancement (18-fold) in the oxidation peak current at ZnO@f-MWCNT, 10-fold at f-MWCNT, and 6-fold at ZnO NPs as compared to that at bare GCE. Under optimised conditions, a linear relationship was noticed among the peak current and concentration of DAS in the range of 0.03-82.65 μM and 0.01-122.45 μM for the differential pulse voltammetric (DPV), and square wave voltammetric (SWV) methods, respectively. Further, the applicability of the proposed sensor was demonstrated by analysing pharmaceutical and biological samples containing DAS. Higher percentage recovery values, and lower relative standard deviation (RSD) values highlighted the proposed electrochemical methods, accuracy, and precision.