Abstract: Molybdenum disulfide nanosheets (MoS₂ NS), a novel class of two-dimensional transition metal dichalcogenides, possess a high specific surface area, excellent photoelectric and photothermal conversion performance, tunable surface chemical activity, and good biocompatibility. These features support their broad application prospects in electronics, energy storage, photocatalysis, and biomedicine. Meanwhile, their potential health risks have become increasingly evident. This review provides a concise overview of the structural characteristics and exposure risks of MoS₂ NS, and summarizes their enrichment characteristics and toxic effects in major target organs including the liver, lung, intestine, and heart. It highlights the mechanistic roles of key molecular events, including oxidative stress, inflammatory response, and ferroptosis in the development of MoS₂ NS-induced toxicity.