A new structure based on carbon nano-tubes (CNTs) and nano-gold particles is presented for surface enhanced Raman scattering (SERS) substrate. By chemical vapor deposition (CVD) method and spin coating, CNTs arrays and films are prepared. Different sizes of gold sol are obtained through chemical reduction method. Order and disorder CNTs are modified. After the decorating, the CNTs and nano-gold particales samples are conducted as SERS substrate. In the experiment, R6G is served as the detecting molecule. Raman spectrum measurement indicates that the Raman intensity of CNTs array is higher than CNTs film, because it can absorb more nano-gold particles. These reinforcing effects are reduced while particles′ diameters decrease from 80 nm, which is better than other groups at 65 nm.