Resveratrol (RES) has limited applications due to its poor stability and low bioavailability. Starch fatty acid complexes can improve the encapsulation and protection of RES, but the influence of fatty acid chain length remains unclear. To investigate the effects of different chain-length fatty acids on the stability and release properties of RES loaded in faba bean starch complexes, faba bean starch (FBS) was used to construct binary complexes with four fatty acids, namely decanoic acid (DA), lauric acid (LA), myristic acid (MA), and palmitic acid (PA). Each complex was then used to encapsulate RES, and the resulting FBS FA RES complexes were evaluated for RES loading capacity, molecular spectroscopic characteristics, in vitro digestibility, and 3D printing performance. Both loading capacity and molecular spectroscopy results showed that as the fatty acid chain length increased, the RES loading capacity of the complexes first increased and then decreased, reaching the highest value (47.53%) for the FBS-LA-RES complex formed at a chain length of 12, where the interaction between the complex and RES was the strongest. In vitro digestion results indicated that, compared with FBS-RES (without fatty acid), the introduction of FA enhanced the digestive stability of RES in the FBS-FA-RES complexes, with the highest RES retention achieved by the FBS-LA-RES ternary complex at a chain length of 12, indicating superior structural stability. 3D printing results showed that the FBS-LA-RES complex exhibited high printing accuracy and a shape retention rate of over 90%, demonstrating its potential as a functional food ingredient. This study provides a theoretical basis and technical support for the optimal design of faba bean starch-based composite wall materials and the efficient delivery of RES, thereby promoting the development and application of functional foods.