Effects of dissolved oxygen concentration from 0?2 to 11 ppm on stress corrosion cracking growth rates of 316NG weld metals in pure water at 288uC were investigated. Crack growth rates in the weld metal with a ferrite content of about 6?5 wt-% are higher than those in the weld metal with a ferrite content of about 8?5 wt-% under the same test environments, which increased with increasing dissolved oxygen concentration from 0?2 to 2 ppm. The dependence of crack growth rates on dissolved oxygen concentration in the range from 2 to 11 ppm was affected by the ferrite content in the weld metals.