[en] The corrosion behavior of 316L stainless steel in stagnating liquid lithium at 350℃ for 500h was investigated by self-designed Laser-Induced Breakdown Spectroscopy(LIBS) analysis equipment, SEM, EDX and Vickers hardness. Microstructure analysis shows that the intergranular corrosion of base metal area is obvious, and the thickness of corrosion layer is about 2.7 μm. The hardness of corrosion base material surface is approximately HV234.72, which is approximately 0.78 times lower than that before corroded. LIBS analysis indicated the loss of Ni or Cr occurred in the sample during lithium corrosion, the quantity of lithium element in the corroded zone decreased with depth increasing in the sample, however, the circumstances were reverse for the nickel and chromium element. And penetration depth of liquid lithium in base metal of 316L S.S is approximately 3.5 μm, which is approximately 0.6 times lower than that weld zone. (authors)