With the rapid growth of power load, the problem of low voltage in China has become increasingly prominent in recent years. It is of great theoretical and practical significance to study a low voltage comprehensive control strategy that can ensure its benefits. This paper proposes a low voltage comprehensive control method based on Safety Efficiency Cost (SEC) and improved Information Gap Decision Theory (IGDT). First, taking line transformation, reactive power compensation, transformer voltage regulation and a new substation as the treatment measures, a mathematical expression for a safety efficiency cost index is constructed. Then, considering the uncertainty of load forecasting error, an improved Information Gap Decision Theory (IGDT) is proposed. With the goal of minimizing the life cycle cost and satisfying the expected goal of safety index, voltage deviation index and investment budget limit, a two-layer robust model of low voltage comprehensive management based on improved IGDT is constructed. Finally, an algorithm for solving the programming model is proposed. The simulation results verify the correctness and effectiveness of the proposed method. This work is supported by National Natural Science Foundation of China (No. 51607104).