The fatigue crack growth (FCG) in dissimilar weld metal joints between SA 508 Cl.3 low-alloy steel and AISI 316L stainless steel (SS) was investigated. The dissimilar weld metal joint was made after buttering alloy 82 on the SA 508 Cl.3 side by gas tungsten arc welding (GTAW). Alloy 82 welding consumable was selected to join these two metals. The fatigue crack growth rate (FCGR) in each material in the dissimilar weld metal joint increased in the order: weldment, AISI 316L SS and SA 508 Cl.3, at the same stress intensity factor range, /K. As the crack propagated across the AISI 316L SS and heat affected zone (HAZ) into the weldment or across the SA 508 Cl.3 and HAZ, into the weldment, the FCGR in the HAZ region did not change or decrease, in spite of the increase in /K. The retardation in the FCGR in the HAZ region was discussed in terms of the welding residual stress.