Rapid temperature changes inside the honeycomb panel induce an internal-external pressure difference, leading to face-core debonding. With the increasing threat of directed energy weapon, understanding their thermal debonding behavior is crucial for structural integrity and defense system design. In this work, a thermal-mechanical coupling failure analysis was conducted to investigate the failure mechanisms of honeycomb panels under directed laser irradiation. Heat transfer theory and the cohesive zone model (CZM) were applied to predict thermal debonding under moderate power laser irradiation. The findings reveal that, under identical laser spot sizes and peak power densities, flat-top laser irradiation leads to significantly larger debonded areas and more pronounced bulging compared to Gaussian laser irradiation. The face-core debonding of the honeycomb panel under moderate power laser irradiation is caused by the combined effects of adhesive layer softening and air expansion inside the cells. These results provide insights into the debonding mechanisms of honeycomb structures and offer guidance for improving their laser-damage resistance.