The advantages and disadvantages of the polytypic BOM storage structure are analyzed. It also gives out a practical storage structure model of BOM. Two basic algorithms of traversal of BOM are summarized, which are recursive algorithm and hierarchical traversal algorithm. Based on the two basic algorithms of traversal of BOM, the generation strategy of product structure tree and the summary strategy of product parts needed are proposed. And the BOM of elevator components is realized for a specific example. The result shows that it is helpful for reducing the storage redundancy of database, system overhead and the complexity of product traversal algorithm by using reasonable storage structure and optimized BOM traversal algorithm.