The crystals of [WS (CuNCS) ] anion have been isolated from CH ,CI solution and examined by X-ray structural analysis as well as by IR spectroscopy. The unit cell is monoclinic with a= 14.3796(13), b= 18.039(1 I), c= 22.5956(23)& P= 96.053(8)', space group P2,/n (14), Z= 4. The crystal structure was refined by the least-squares calculations to a final R-value of 0.0398(Rw= 0.0443) for 2777 unique observed reflections [F>3o IFI].