Copper sulfide nanowire arrays(NWAs)have attracted great attention due to their better conductivity than the corresponding metal oxide as electrode materials in energy storage [1,2].Herein,we introduce a facile ion exchange reaction for direct growth of top-bundling Cu1.8S NWAs with interconnected structures on copper foam,involving in-situ pregrowth of Cu(OH)2 NWAs.The Cu1.8S nanowires are contacted together of their tops,which is quite similar to the radial ribs of umbrella and form an interconnected structure.