The effect of strain rate on stress corrosion cracking of 316LN SS in borated and lithiated(B/Li)high temperature water was studied.The results showed that SCC occurred only in a certain strain rate range,and the elongation and the average cracking growth rate increased as the strain rate increased in the range.Additionally,the upper critical strain rate for producing SCC was obtained and the average cracking growth equation was established.Stress corrosion cracks of 316LN SS initiated in slip bands or Cr-depleted zones at the surface and propagated in the base metal transgranularly.