A kind of nonfilling polyaniline coating of sulfur/acetylene black composite is prepared via a facile and eco-friendly approach in consider of the different solubility of sulfur in the liquid phases and at the proper temperature. Acetylene black particles with the particle size of 50 nm are partially infiltrated with sulfur, just the outer surface are coated with polyaniline shell. When using as a cathode material for lithium sulfur batteries, it exhibits significantly enhanced rate capability (initial capacity of 810 mAh/g at 2C, 486 mAh/g at 5C), and rate stability after 500 cycles (> 351 mAh/g at 5C). This considerable electrochemical performance could be attributed to the highly uniform distribution of sulfur in the nanopores of the conductive acetylene black and the physical isolation of the sulfur with electrolyte by conductive polyaniline. This renders it to be a promising candidate for practical application in lithium sulfur batteries.