An optimized design, in accordance with the standards as required by resource-based, environment-friendly and industrialized intelligence substations, has been made of 110 kV substations in Chengguan District of Chaling County. This optimized method mainly involves an improved design of the overall layout and device selection optimization, followed by a comparison between characteristics of the improved design and the conventional one. By calculation, the gross floor area for the improved design accounts for only 53.39% of what the conventional design requires, and reduces the static investment by 20.30% correspondingly. The optimized method fulfills the compact layout as well as decreases the investment cost, thus ultimately achieving the goal of the substation optimization.