This paper presents a transportation and distribution model of emergency materials for a three-layer relief
transportation network after analyzing the practice of emergency management. The model aims at minimizing the system
losses and meets the constraints of emergency response time and fairness constraint. A modified particle swarm optimization
algorithm is proposed for the integer nonlinear programming，the spatial search abilities of the particles are improved by
determining different learning objects for different dimensions of the particles. Finally, a numerical example verifies the
effectiveness of the model and the algorithm.