The growth process of the single-walled carbon nanotubes (SWNTs) during chemical vapor deposition is monitored by in-situ Raman spectroscopy.Since a Raman spectrum taken at high temperature usually has very low intensity, which is unable to provide enough signal-to-noise ratio to explicit the fingerprints of the obtained material [e.g.shape of G-peak or even radial breathing modes], we are devoted to explore the possibility of increasing Raman signal using metal nano-particles mediated surface enhance Raman scattering (SERS).