n-butyl mercaptan modified molybdenum disulfide nanosheets (MoS2-C4) are synthesized by simple one-pot method. The structure, component, morphology and electrical bistable properties of the samples are investigated. In the reaction process, n-butyl mercaptan is not only used as a sulfur source but also used as the surfactant. X-ray diffraction (XRD) test indicate that the obtained sample is MoS2 with hexagonal system. The sheet-like morphology is confirmed by the transmission electron microscopy (TEM) and atomic force micros (AFM). And the bigger nanosheets are self-assembled by the lesser nanosheets. The absorption spectrum of the sample is tested and the location of absorption peak reveals that the sample is 2H-MoS2. Electrical bistable device is fabricated by the mixture of prepared nanosheets and polyvinylcarbazole (PVK). And the device exhibits obvious electrical bistability by I-V test.