In order to effectively improve the power generation efficiency of large wind turbines, studies on the optimization measures for the aerodynamic performance of wind turbine airfoils were conducted. Wind tunnel experiments were conducted to systematically investigate the Reynolds number effects on the aerodynamic performance optimization of wind turbine airfoils with vortex generators in a continuous high Reynolds number range. The results indicate that as the Reynolds number increases, the airfoil lift coefficient exhibits a significant upward trend. The Reynolds number effect is evident regardless of whether vortex generators are installed or not. The positioning of the vortex generators significantly affects their Reynolds number effect on aerodynamic performance optimization. When the vortex generators are placed within the range of 0.1c to 0.2c [WTBZ] from the leading edge of the airfoil, the improvement in the lift coefficient is significantly better than when they are placed within the range of 0.3c to 0.4c from the leading edge. This improvement increases gradually with the increase of Reynolds number, but the increasing trend is not linear. When the vortex generator is placed within the range of 0.3c to 0.4c from the leading edge, the lift coefficient improvement decreases with the increase of Reynolds number, and there exists a critical Reynolds number. Based on this, a formula is derived to represent the vortex generator's effect on airfoil aerodynamic performance optimization under different Reynolds number conditions, which can provide reference for engineering purposes.