The rapid qualitative and quantitative analysis of melamine in pet food was realized by surface-enhanced Raman spectroscopy in combination with Ag nanoparticle. In the present study, the 709 and 1 542 cm-1 Raman shift was chosen as qualitative basis. The quantitative calculation of the concentration range between 1.0 and 10.0 mg·kg-1 was achieved based on the intensity of 1 149 cm-1 Raman peak which was used as a normalization standard. The limit of detection was 0.5 mg·kg-1. The Ag nanoparticle had a strong Raman enhancement effect on melamine and the intensity was affected by the adding time of Ag nanoparticle and the vortex strength. At the same time, the intensity of SERS was affected by the extraction solvent type, and the manner of extracton. The analysis time of each sample was about 5 min. It was so quick that it was easy to realize the rapid detection of melamine in pet food compared with existing methods.