Using sulfur powder and MoO3 powder as raw materials, the MoS2 film was synthesized by chemical vapor deposition method, and was characterized by optical microscopy, atomic force microscopy, raman spectroscopy and X-ray diffraction. Results show that the crystal morphology of the MoS2 is triangle with size of 60 μm and thickness of 0.7 nm; and as one kind of the ideal substrates for surface-enhanced Raman scattering, two-dimensional MoS2 can promote the charge transfer between the organic molecule and MoS2, so the Raman intensity of them are enhanced. The pentacene was adsorbed onto the MoS2 film by physical vapor deposition method, and the organic-inorganic pentacene/MoS2 heterojunction with ideal rectifier characteristic was prepared. Analysing the ln(I/V2)-1/V curve, it is seen that the Fowler-Nordheim tunnelling phenomenon occured through the heterojunction; logI-logV curve shows that charges transport controled by ohmic conduction at 0~1 V voltages zone, and space-charge-limited currents predominate at over 1 V voltages zone. The research of MoS2 single-layer film and pentacene film will be contributed to the optoelectronic field.