A fast and efficient way to synthesize a　large　number　of　silver　nanowires　was developed in this paper, in which the reaction conditions were optimized. Under the protection of Cu(NO3)2 silver nitrate was reduced by polyol with polyvinyl pyrrolidone (PVP) in existence. The silver nanowires with uniform structure and good dispersion were obtained.　Surface enhancement activity of the silver nanowires was detected by using RhB as a probe molecule, its surface enhancement factor can reach 6.4×105. The results showed that the nanowires significantly enhance the Raman spectroscopy of RhB. The normal Raman　spectroscopy　(NRS), Raman spectroscopy of D-carnitine　solution and Surface enhanced Raman Spectroscopy of D-carnitine by means of the new base were obtained. There are obvious Raman peaks at 3　100～2　800 and 1　700～200 cm-1, and the peak of 1　700～200 cm-1 in the surface enhanced Raman spectra of the D-carnitine can be obviously enhanced. The analysis showed that the angle between the molecular and silver nanoparticles were 180°.　The vibrational peaks were assigned comprehensively.　Compared with the NRS and SERS of D-carnitine, the detailed structural information of D-carnitine was obtained. In this paper, the surface enhanced Raman spectra of the D-carnitine absorbed on the synthesized silver nanoparticles were obtained, and the minimum detection concentration was 10-6 mol·L-1.　The new method can be a rapid and characteristic way to detect D-carnitine, and it will also provide an important guidance for the studies on pharmacology of D-carnitine.