The APO is a superior algorithm with global search capability, and it can avoid premature convergence that easily occurs in Particle Swarm Optimization (OPS) and other algorithms. Besides, it has better stability, rapidity convergence and robustness. Aimed at reactive optimization problem of hybrid AC-DC system, and according to the APO of the vector model, a reactive optimization algorithm is proposed based on a kind of improved APO. In order to solve the restricted problem, the algorithm defines infeasibility degree function to judge infeasible solutions, haul the infeasible solution back to the feasible zone by use of the constriction factor, and search the optimal solution based on multidimensional search algorithm. According to the simulation test of IEEE 30-bus system, and compared it with other algorithms, it turns out that the improved APO is accurate and efficient in searching the solutions.