Uniformity of microstructure and mechanical properties is required for the heavy section steel. In the present work, a heavy section wind tower flange was manufactured by controlled ring-rolling. Post-rolling heat treatment was employed to optimize the microstructure and mechanical properties. The chemical composition, microstructure and mechanical properties in different zones of the flange were investigated. The results showed that the chemical composition and microstructure were uniformly distributed in the flange. The tensile strength showed similar values in different sampling locations. The strain and impact energies of specimens prepared along the longitudinal direction were higher than that prepared along both the radius and thickness directions. Notch direction did not have noticeable effect on the impact energy. It is demonstrated that the designed process is effective for producing heavy section steel with improved quality.