To solve the premature convergence problem of Particle Swarm Optimization (PSO), a new algorithm named DE-PSO (Double-population Evolution-Particle Swarm Optimization) was designed. DE-PSO introduced selection, crossover and differential mutation into PSO, and adopted a new evaluation method to evaluate swarms and a new control method to ensure all swarms can fly inside search space. DE-PSO was applied to solve two groundwater management cases. Two case studies indicated that DE-PSO could evolve steadily, the searching efficiency was better than GA, SA and PSO. DE-PSO could solve groundwater management model problems effectively.