Hydrogen energy is the most promising renewable energy, and electrocatalytic water splitting to hydrogenproduction is an efficient and environmentally friendly way. More importantly, a high-efficiency catalystfor both hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are urgentlyneeded. The low cost, large specific surface area, high electrical conductivity and abundant surface functionalgroups, zero-dimensional quantum dots have emerged, such as Carbon quantum dots (CQDs)/Graphene quantum dots (GQDs), Black phosphorus quantum dots (BPQDs), MXene-derived quantum dots(MXQDs). The catalytic performance of traditional transition metal-based electrocatalytic is not goodenough, and the introduction of quantum dots increases the electrical conductivity, energy conversionefficiency and a large number of catalytic active sites of the composites, which significantly improvesthe electrocatalytic performance of the composites. Fast charge transfer rate and large specific surfacearea make quantum dots become functional materials for electrocatalytic energy conversion, and richfunctional groups can provide rich binding sites and active sites for multi-component composites. Furthermore, quantum dot-based composites with excellent comprehensive properties have broad applicationprospects and can be applied to advanced fields such as fuel cells and supercapacitors related toenergy storage and conversion.