Reviewing the passive design changes and optimization problems that occurred during the development of a certain type of civil aircraft, the main reason is that the design plan of the crew warning and indication does not fully meet the pilot’s operational needs. In the early stage of the warning system design, there is a lack of alarm requirements confirmation means and the difficulty of insufficient demand confirmation. If the correct modeling and evaluation plan can be used in the early stage of the warning system design, problems can be found in time and major problems can be avoided in the later stage. Aiming at this problem, this paper first elaborates the relationship between alarm requirements and failure modes, builds an alarm requirement database for the characteristic information of alarms, and captures the criteria according to alarm requirements. Taking the hydraulic system function operation model as an example, obtain the failure mode that needs to be alarmed through the system failure mode analyzing and the mapping relationship between the models, finally combining the model experience and the alarm concept in ARP41024, FAR25.1322 and AC251322 to complete the system alarm definition.