In order to improve the seismic reliability analysis efficiency of water supply pipe network based on Monte Carlo simulation, the failure probabilities of water supply pipe network nodes and pipes were sampled by using low discrepancy Sobol sequence instead of pseudo-random number sequence. Combined with the breadth-first search algorithm, a parallel algorithm for seismic reliability analysis of water supply pipe network based on quasi-Monte Carlo method and compute unified device architecture (CUDA) was proposed. The parallel algorithm was optimized from the aspects of memory, execution configuration and instructions. A city water supply pipe network was taken as the computational example, the accuracy and efficiency of serial and parallel computing methods were compared, and the influence of Sobol sequence and pseudo-random number sequence on the reliability analysis of pipe network was analyzed. Results show that the maximum error of the parallel and serial methods is 0.52%. The maximum acceleration ratio of the parallel method is 96 times that of the serial method, and the parallel method significantly improves the computational efficiency while ensuring the accuracy of results. 1 000 parallel simulations were performed based on Sobol sequences and 5 000 parallel simulations were performed based on pseudo-random number sequences, and the maximum errors between the two simulation results and the analytical value based on fuzzy mathematics were 0.2% and 0.4%, respectively. It indicates that the parallel method based on quasi-Monte Carlo has higher accuracy and faster convergence speed.