The voltage regulating problem in distribution networks with distributed generators connected is modeled as multi-objective optimization, which is aimed to improve the voltage quality, reduce active power losses and restrict the voltage variations by adjusting the tap-changers and switching shunt capacitors. The three objectives are evaluated by membership functions respectively, such that the satisfaction of different objectives can be compared. To facilitate the solving process, a compromised objective is formed by the weighted sum approach. The weightings of the objectives are determined by the fuzzy judgment matrix, which is constructed by the relative importance between every two objectives. The active tabu search algorithm is employed to obtain global optimization solutions. Simulation results show that the method proposed is effective in improving the voltage profiles while reducing power losses.