Abstract：The prepared silver nanoparticles synthesized by chemical method was bound with lysine at different pH values. The UV-Vis spectrum and dynamic light scattering methods were used to study the stability of Ag colloids and AgNPs-lysine system. The interaction of Ag nanoparticles and lysine was surveyed by SERS. The results showed at the pH value of 5~10, the UV-Vis spectra appeared strong adsorption peak, the particle size was uniform distribution and DLS intensity auto-correlation curve was smooth, which indicated that the system had good stability. The interaction of lysine binding to Ag nanoparticle surface was investigated by SERS. At the pH value of 4, the SERS band at 1440 cm-1 is assigned to δ (NH3+), and the band of 1576 cm-1 is assigned to δ (COO-) , which tells the lysine adsorbs on the Ag sruface through the interaction of the amino and carboxyl groups together. At the pH value of 10, the main characteristic Raman spectrum was δ（COO-）at 1576 cm-1, it demonstrated that the lysine was adsorbed on the surface of silver nanoparticles with the NH3+ group.