Scarf adhesive joints (SAJs) have attracted an increasing attention in joining/repairing of carbon-fiber reinforced epoxy (CFRE) composite structures due to their zero eccentricity, which provides better aerodynamic surfaces. This study evaluated for the first time, the performance of SAJs in CFRE composites under thermo-mechanical impact loads. The adhesive was modified with optimum percentage of multi-walled carbon nanotubes (CNTs). The impact tests were performed at room temperature of +25C, +50C and +75C. The residual flexural properties of the unfailed impacted joints were measured using three-point bending test. Results from impact tests at temperature of 25C, 50C and 75C showed improvement in the impact bending stiffness of the modified SAJs with CNTs by 8.3%, 7.4% and 11.8% and maximum contact force by 15.6%, 21.3% and 18.9%, respectively. The energy at failure of the CNT-SAJs was increased by 15.2% and 16.4% respectively at temperatures of 25C and 50C. At test temperature of 75C the SAJs have hysteresis load-displacement behavior and energy-time curve with rebound energy of 35% and absorbed (damage) energy of 65%. The residual flexural strength of the modified and unmodified SAJs is 98.2% and 86.1% respectively, while their residual moduli have remarkable decrease to 71.7% and 81.3%.