In order to improving the power and efficiency of a single heavy-duty gas turbine, it is imperative to address the technical issues in turbine cooling design. Based on the practices of some international heavy-duty gas turbine manufacturers, the fundamental ribs and pin-fins cooling configuration was obtained. The average Nusselt number of the heat exchange surface was set as the optimization target, and the composite ribs and pin-fins cooling configuration with enhanced heat transfer performance was obtained through the genetic algorithm. The results indicate that the continuous V-rib exhibits superior heat transfer performance compared to the discontinuous V-rib. However, when the continuous V-rib and the discontinuous V-rib were integrated, the new configuration with even better heat transfer performance has occured, and the comprehensive heat transfer factor can be elevated by 14.6% to 18.2%, including one cooling channel with a lower friction factor and another with a higher average Nusselt number.