The development of an advanced electrocatalyst is crucial to achieve low-cost and efficient biomass electrooxidation for assisting its practical application. In this study, we design a unique heterostructure of Mo-doped Co(CO3)0.5OH coating on NiCo2S4 nanowires for efficient xylose oxidation reaction (XOR). The as-prepared electrocatalyst requires only 1.28 V for XOR to achieve current density of 50 mA cm−2, and the electrocatalytic system exhibits the high formic acid (FA) yield of 63.22 % and excellent selectivity of 96.52 %, which still maintains unchanged after seven cycles. Furthermore, the two-electrode system by coupling XOR and hydrogen evolution reaction (HER) shows that product selectivity remained at least 96 %, while the hydrogen production rate higher than the original. This remarkable performance is attributed to the synergic effect of heterostructure and multi-component as confirmed by XPS and XRD analysis. This work puts forward an attractive approach for designing high electrocatalytic activity and selectivity electrocatalyst for biomass electrooxidation.