To provide a device and a method for chemical and mechanical polishing capable of relatively high and uniform polishing speed by improving the controllability of polishing.

A chemical and mechanical polishing device 10 includes a mixing part 12 where polishing fluid components are mixed with each other before polishing fluid is led into a polishing part 13 of the polishing device 10. In one embodiment, some components from feed lines 113 and 114 are mixed with each other in a manifold 121, and mixed through a static in-line mixer 123 to form polishing fluid. Because the mixing is made near a site where the fluid is used, the polishing rate of the polishing fluid is relatively high. A local concentration of the components of the polishing fluid near the substrate 134 is relatively uniform because the polishing fluid is mixed before it reaches near a substrate 134.