Rainwater pipeline network is an important part of urban drainage engineering system. Optimal reconstruction of the pipeline network scientifically and economically is the key to improving the capacity of its drainability and effectively relieving urban waterlogging disasters. In order to achieve this goal, a pipeline network optimal reconstruction model based on multi-objective optimization (NSGA-II) was established in this paper. There were three objective functions in this optimal reconstruction model including construction cost, drainability, and quantities. In addition, by invoking program source code, the paper realized automatically executing SWMM for hydraulics simulation. At last, the paper took a case for application whose results showed that this optimal reconstruction model could get feasible reconstruction plans and would have some referential value.