Supported tungsten carbide is an efficient and vital nanomaterial for the development of high performance, sensitive and selective electrochemical sensors. In this work, tungsten carbide with tube-like nanostructures (WC NTs) supported platinum nanoparticles (PtNPs) are synthesized and explored as an efficient catalyst towards electrochemical oxidation of oxalic acid for the first the time. The WC NTs supported PtNPs modified glassy carbon electrode is highly sensitive towards the electrochemical oxidation of oxalic acid. A large decrease in the oxidation overpotential (220 mV) and significant enhancement in the peak current compared to unmodified and Pt/C modified GC electrodes have been observed without using any redox mediator. Moreover, WC NTs supported PtNPs modified electrode possessed wide linear concentration ranges from 0 to 125 nM, and a higher sensitivity towards the oxidation of oxalic acid (80 nA/nM) achieved by amperometry method. The present modified electrode showed experimentally determined lowest detection limit (LOD) of 12 nM (S/N=3). Further, WC NTs supported PtNPs electrode can be demonstrated to have an excellent selectivity towards the detection of oxalic acid in presence of 200-fold excess of major important interferents. The practical application of WC NTs supported PtNPs has also been demonstrated the detection of oxalic acid in tomato fruit sample, by differential pulse voltammetry under optimized conditions.