A method and device for monitoring an avionics software application via its execution duration, related computer program and avionics system are disclosed. In one aspect, the method, executed on a platform hosting an operating system, is implemented by an electronic monitoring device. The avionics software application includes one or several software processing operations to be executed, the platform is configured to be on board an aircraft. The method includes: monitoring the execution duration of the avionics software application, through the verification, upon expiration of at least one predefined execution times, of the completion of the execution of at least one software processing operation of the avionics software application; and updating a status of the avionics software application based on the monitoring of the execution duration of the avionics software application.