Abstract: An overpressure indicator is defined by a housing sized and configured for attachment within a compartment interior, such as an aircraft nacelle. A pressure sensing element disposed within the housing is coupled to an indicator element and is configured to detect a pressure differential between the interior and exterior of the compartment. The indicator element is caused to move in response to a predetermined change in pressure exceeding a threshold pressure differential. The indicator element includes a distal end that is moved to a position exterior of the housing and the compartment, providing a visual indication of an overpressure condition. A reset feature provided on the indicator can only be accessed by first opening the compartment in which the indicator has been mounted. A spring can be provided to assist in the triggering of the indicator member after the threshold pressure differential has been detected.