Various stacking patterns have been predicted in few-layer MoS 2, strongly influencing its electronic properties. Bilayer MoS 2 nanosheets have been synthesized by vapor phase growth. It is found that both A-B and A-A′ stacking configurations are present in bilayer MoS 2 nanosheets through optical images, and the different stacking patterns exhibit distinctive line shapes in the Raman spectra. By theory calculation, it is also concluded that the A-B and A-A′ stacking are the most stable and lowest-energy stacking in the five predicted stacking patterns of bilayer MoS 2 nanosheets, which proves the experimental observations.