For integration of hydrogen networks by mathematical programing, the utilization of a dedicated compressor in each match of hydrogen source and hydrogen sink can avoid the non-linear terms arising from the mixing inlet streams and the unknown pressures of compressors, which greatly reduced the complexity in solving the hydrogen network optimization models. However, it may lead to large number of compressors and higher capital costs. To solve this problem, a method of compressor merging is proposed in this work, in which two strategies of merging compressors are proposed, namely, the hydrogen sources oriented compressors merging strategy (HSCM) and the hydrogen sinks oriented compressors merging strategy (HKCM). The proposed strategies consider the upper capacity bound of a compressor and the capital cost of the compressors, and do not change the optimal matches of hydrogen sources and hydrogen sinks. A case study is employed to exemplify the implementation of the proposed method. The results show that the proposed strategies can reduce the number and the capital cost of compressors effectively. And the operating flexibility of the hydrogen network is also improved.