Several studies have suggested that the Aerodynamic Foil Journal Bearing experiences a significant temperature rise. However, the role of viscous dissipation on this bearing, especially with the Aero-Thermo-Elastic coupling effect, has not yet been clarified. This study aims to investigate the effects of viscous dissipation on the flow field and aerodynamic heating in an aerodynamic foil journal bearing with fluid-structure interaction at an eccentricity ratio of 0.6 and a nominal clearance height of 100 µm. The results show that the conjugation of Aero-Thermo-Elastic plays a significant role in the flow field and temperature distribution. In the rigid case, a significant temperature rise is observed near the minimum clearance height when viscous dissipation is considered, which is 17-24 K higher than the case without viscous dissipation. Furthermore, coupled with the Aero-Thermo-Elastic effect, the temperature rise with viscous dissipation is higher than the case without viscous dissipation (about 16-20 K higher), and the static pressure in the clearance is also larger (about 30 Pa higher). However, when the structural damping is small, the fluid domain exhibits periodic variations. The temperature variation with time under consideration of viscous dissipation is less than that without considering viscous dissipation. Similarly, the pressure variation with time under consideration of viscous dissipation is also less than that without considering viscous dissipation. Within the scope of this study, the temperature rise induced by viscous dissipation dominated the flow field and temperature distribution in the Aerodynamic Foil Journal Bearing. The temperature rise induced by variation of flow channel becomes significant only in the Aero-Thermo-Elastic coupling case.