According to the characteristics of order picking problem in DC, with customer’s satisfaction as the objective, a mathematical model was established and corresponding Genetic Algorithm (GA) was designed to solve this problem. In the example, a comparison was made between GA and the two dispatching rules of First Come First Service (FCFS) and Earliest Due Date (EDD). The result showed that GA can apparently optimize the value of objective function, improve efficiency of order picking and satisfaction of costumer, and has good usability in the order sequencing problem.