The present study has been performed to explore the detailed configuration of the local reaction zone of a high intensity turbulent premixed flame by using a micro-electrostatic probe of two identical sensors. The local reaction zone configuration is shown to be determined by analyzing the ion current fluctuations. The radius of the local reaction zone curvature convex toward the unbumed mixlure is larger than that convex toward the burned gas. The radii of the local reaction zone curvature convex toward unburned mixture are distributed over a wider range than those convex toward burned gas. The frequency of the larger radius of the local reaction zone curvature increases in the downstream region. Therefore, the mean radius of the local reaction zone curvature in the downstream region is larger than that in the upstream region.