This paper presents a genetic algorithm-based approach for short–term scheduling of reactive power controllers. The objective of this paper is to determine the proper settings of the control devices (capacitor banks and transformer taps) for the next 24 hours, which minimizing the active power losses without exceeding the allowed number of movements of the control devices per day, and maintaining satisfactory voltage profile under various loading conditions. A genetic algorithm (GA) approach is proposed in this paper. The GA algorithm is applied into two levels, at the first level, GA is implemented to determine the optimal reactive power dispatch (optimal settings of control devices) for each operating hour in the day, and then at the second level, GA is implemented again to find the final optimal reactive power dispatch for the whole day. The proposed method was applied to a modified IEEE 30-bus system to show the feasibility and the capability of the proposed method, the experiment was carried out and the results are presented in this paper.