For the purpose of improving the general properties of gelatin films, fish-scale gelatin edible films were modified by glycosylation and myricetin. The results showed that glycosylation and myricetin collaboratively strengthened the edible mechanical properties and ultraviolent light prevention characterizations without influencing the water barrier capacity of the film. The myricetin improved the water barrier capacity of the film while glycosylation reduced that capacity. The results of DSC and SEM indicated that cooperative synergism improved the film thermal stability, smoothened the surface and made internal structure more regular and compact compared with modification by only one of them. Analysis of FTIR and secondary structure content demonstrated that, both myricetin and glycosylation could separately alter fish-scale gelatin molecular structure through hydrogen bonds and inter-molecular interaction. Complementation of two modification ways caused that β structure converted to α helix and random coil , which did not significantly affect the water barrier capacity, but collaboratively optimized mechanical property of the composite film. The combination of myricetin and glycosylation provided a potential approach to improve gelatin film performance.