The operational conditions of hydrogen networks in practical refineries commonly fluctuate due to variation of feed properties, loss of catalyst activity, change of market demand, seasonal shift, and improvement of processing technology as well. These fluctuations could affect the operations of the hydrogen networks, which are usually optimized on the basis of fixed operational conditions in practice. In this work, a flexible design method of a multiperiod hydrogen network is proposed. It features the flexible design of multiperiod hydrogen network by considering discrete operational scenarios in multiple periods and possible fluctuation of each operational scenario. The optimal design of the multiperiod hydrogen network with simple structure and low total annual costs can be obtained by the proposed method. Moreover, the bottlenecks restricting the flexibility of each subperiod can also be identified and eliminated. In addition, the proposed method can be readily implemented. A multiperiod hydrogen system in a refinery is used to exemplify the proposed method. The results show that the proposed method can be used to effectively obtain the hydrogen network structure that satisfies the multiperiod operational conditions and reach the flexibility requirements for each subperiod with the lowest total annual costs.