Human reliability analysis (HRA) is an important part of probabilistic safety assessment (PSA). With the wide application of advanced technology in nuclear power plant, team members share the information. The failure of previous human failure events may increase the human error probability of the following human failure event. Therefore, in the human reliability analysis, it is necessary to evaluate the dependency between human failure events and modified the human error probability of the following human failure events. The lack of dependency analysis would seriously underestimate the risk level of nuclear power plants. HRA dependency analysis is very important, it can directly affect the quantitative results of PSA and HRA, not only greatly affect the value, but also affect the risk distribution. PSA regulations and standards require the dependency analysis of HRA, but there is lack of special technical documents of HRA dependency analysis in China. There are four existing problems and difficulties in HRA dependency technology in the Nuclear Power Plant: 1. There is no unified evaluation process to conduct the dependency analysis of HRA; 2. The existing methods to obtain the human failure events group in the same cut-set are easy to miss some important dependency groups. 3. The judgment basis of some dependency indexes needs to be adjusted and optimized, and there is a lack of zero dependency criteria. 4. The dependency of between Level-1 PSA and Level-2 PSA is not taken into account. This paper intends to study and solve the existing problems and difficulties, in order to form a set of comprehensive and widely recognized HRA dependency analysis methods and processes, in order to better guide and standardize the HRA dependency analysis, providing technical support for the development of high-quality PSA model and the application of license documents, which has important scientific research and engineering application value to the risk-informed design to the Nuclear Power Plants.