Two dimensional MoS₂ nanosheets decorated with inorganic nanoparticles (INPs) are emerging as novel MoS₂-based nanohybrids for tuning the intrinsic attributes of both components for fundamental research and technological applications. However, the design and fabrication of MoS₂–INP nanohybrids with a tailor-made structure and functions remain a significant challenge. Herein we report a general and controllable protocol for the one-step synthesis of various MoS₂–INP nanohybrids by employing carboxylic MoS₂ (MoS₂–COOH) nanosheets as a versatile support. The obtained MoS₂–INP nanohybrids exhibit good dispersibility, high reactivity and excellent processability. The size, morphology and coverage density of INPs on the surface of MoS₂–COOH can be readily controlled by tuning the feed ratio. Control experiments reveal that the presence of carboxylic functional groups plays a key role in controlling the structure and properties of the resulting MoS₂–INP nanohybrids. In addition, ternary MoS₂-based nanohybrids can also be readily prepared by this approach, as exemplified by the synthesis of MoS₂–Fe₃O₄/Pt nanohybrids, which simultaneously exhibit excellent catalytic performance toward the reduction of 4-nitrophenol and favorable magnetic separation capability. Considering the simple fabrication process, high controllability of this protocol and excellent performance of the product, the present work opens up enormous opportunities for the large-scale production of diverse MoS₂-based nanohybrids for many technological applications.