The design problem of two-dimensional recursive digital filters is generally reduced to a constraint minimization problem. Based on our previously proposed Quantum-Behaved Particle Swarm Optimization (QPSO) algorithm, inspired by quantum physics, we proposed an improved QPSO, called Diversity-Guided QPSO (DGQPSO) to obtain the solution of the design problem. The DGQPSO is implemented by controlling the diversity measure of the swarm to enhance global search ability of the QPSO. The results yield by DGQPSO in design problem show its superiority compared to other competitive optimization algorithm.