In this work, the 2D nanostructured h-BN/WS2 heterojunction was successfully prepared by the hydrothermal method-assisted exfoliation of bulk h-BN and WS2. The morphology and structure of the as-prepared heterojunction were determined by a series of characterization techniques. The mechanism for the formation of the as-prepared heterojunction was proposed. The friction coefficient and wear rate of the as-prepared h-BN/WS2 heterojunction-grease was decreased by 33.9％ and 45.9％, respectively, as compared to those of the neat grease.