In crisis scenarios, trust and knowledge sharing are rare and crucial for moderating the relationship between leadership and performance. This paper examines how leadership influences the performance of civil servants during crises in the public sector, mediated by trust and knowledge sharing. The authors develop a theoretical model and empirically test it with survey data from 346 civil servants in the public sector related to epidemic response in China. A structural equation model is used to examine the paths through which leadership affects performance. This research indicates that crisis leadership can directly enhance contextual performance but does not directly impact task performance. However, both explicit and tacit knowledge‐sharing behaviour can exert significant mediating effects. Furthermore, cognition‐based trust can indirectly influence task performance through a chain mediation effect involving explicit knowledge sharing. This research underscores the multifaceted impact of crisis leadership and elucidates how leaders can effectively navigate crises through different types of trust and knowledge‐sharing strategies.