Curcumin (diferuloyl methane or 1,7-bis(4-hydroxy-3-methoxy-phenyl)-hepta-1,6- diene-3,5-dione) has been reported as a bioactive compound that exhibits antioxidant activity. The aim of this research was to investigate the modified structure of curcumin with cinnamaldehyde and malononitrile in the presence of guanidine as catalyst under Knoevenagel reaction with different pH and catalyst concentration and its application in edible film. The reaction took place under different pH of 5, 8, and 10. This study showed pH 8 was preferable for curcumin modification which resulted in the highest antioxidant activity of IC50 30.1999±0.6244 mg/L. The chosen modified curcumin was compared to commercial curcumin and showed higher antioxidant activity and shifting to longer wavelength in UV-Vis spectrum. Guanidine as catalyst at concentration 10, 20, and 30% showed no different effect on yield, antioxidant activity, and UVVis characteristics of modified curcumin. The chosen modified curcumin was characterized for the chemical structure and mass spectrum by using FTIR, GC-MS, and LC-MS. The results showed there were changes in the chemical structure and mass of modified curcumin. The modified curcumin was applied to edible film at different concentration of 0, 0.1, 0.2, and 0.3%. The edible films were analyzed for the antioxidant activity and the mechanical characteristics. Based on the result, edible film with addition of 0.1% modified curcumin was chosen which had IC50 of 4,892.8142±141.8264 mg/L, tensile strength of 1.9723±0.1117 MPa, elongation at break of 23.6318±1.5538%, water vapor transmission rate of 0.1616±0.0086 g.mm/m2.h, and thickness of 0.1050±0.0055 mm.