Thermodynamic analysis that provides the status and amount of irreversibility is a powerful tool to determine performance parameters of energy conversion systems. However, specifying the location and amount of irreversibility of a system or component does not reveal the full extent of the relationship of the irreversibility between component-component/component-system. Therefore, splitting the exergy destruction into endogenous and exogenous parts provides detailed information on the relationship of the irreversibility between component-component/component-system. The purpose of this paper is to identify the endogenous and exogenous parts of exergy destruction of an experimental turbojet engine (Unmanned Aerial Vehicle Turbojet - UAVT). Test data used for exergy analysis were evaluated at the maximum load of the experimental turbojet engine which consisted of a compressor, a combustion chamber and a turbine. As a result of the endogenous and exogenous parts of the exergy destruction, the majority of the total exergy destruction (15.1416  kW) was calculated as the endogenous part of exergy destruction (13.5473  kW), and the exogenous exergy destruction rate was calculated to be 1.5943  kW in the compressor component of the turbojet engine. In this study, the endogenous and exogenous exergy destruction amounts of other components are also presented in details.