Two-dimensional (2D) nanomaterials have aroused immense attention in extensive applications due to their intriguing physical and chemical properties. However, there is a formidable challenge to prepare few-layered and functionalized 2D nanomaterials in an effective and universal way. Herein, we developed an integrated strategy of glucose-assisted mechanochemical exfoliation and cosolvent-intensified sonication exfoliation to effectively exfoliate and functionalize 2D materials. Taking exfoliation of boron nitride (BN) as an example, the production yield and functionalization ratio of BN nanosheets (BNNSs) reached 47.5% and 25.8 wt.%, 188% and 16% higher than that of BNNSs without sonication exfoliation, respectively. The introduction of glucose not only augmented the friction force between adjacent BN layers to promote the efficiency of ball-milling-driven exfoliation supported by density functional theory calculation, but also reacted with active edges of BNNSs for functionalization. Afterwards, cosolvent-intensified sonication exfoliation strongly stabilized exfoliated BNNSs, obviously boosting the exfoliation yield. This proposed method is universal for preparing various 2D nanomaterials like molybdenum disulfide, tungsten disulfide, and graphene nanosheets. The thin plate structure and high functionalization ratio enabled the release of property superiorities of 2D nanomaterials. Our work offers a promising prototype to realize mass production of functionalized 2D nanomaterials.