For braised pork belly, a popular traditional Chinese dish, we lack a scientific knowledge to reduce the formation of harmful heterocyclic amines (HAs) and advanced glycation end products (AGEs) while maintaining sensory quality. This study aimed to clarify the factors affecting the formation of free and protein-bound HAs and AGEs during the braised pork belly cooking process using UPLC-MS/MS analysis. The results indicated that soy sauce significantly promoted the formation of HAs, with organic soy sauce exhibiting the strongest promoting effect, increasing HAs by 270.92 %. Early-middle incorporation of sauce juice can attenuate this promoting effect. Spices exerted an inhibitory effect on HAs and AGEs formation, which was enhanced when added in powdered form, although no significant differences were observed across different dosages. Notably, the elevation of crystal sugar levels reduced both HAs and AGEs while enhancing sensory preference. Several umami flavor enhancers, particularly 5'-flavored nucleotide disodium, further inhibited the formation of these harmful compounds. This research deepens the understanding of the association between seasonings additions and the formation of harmful substances in braised meat products, providing valuable insights for developing safer and healthier culinary practices.