We present a strong Raman enhancement substrate through one-step thermal treatment of bulk MoS 2 . The substrate provides very efficient hot spots by using the rhodamine 6G (R6G) molecule as a probe. Raman and photoluminescence spectra of modified MoS 2 reveal the detailed mechanism for enhancing Raman signal of R6G. It is found that both the substrate roughness and the slight chemical bond broken on the surface are the main driven forces to induce the surface enhanced Raman scattering (SERS) effects. The minimum detectable concentration of R6G on the most optimized thermally treated MoS 2 can be as low as 10 –8 M. This synthetic approach is facile, sensitive, and reliable, which shows great potential to be an excellent SERS substrate for biological and chemical detection.