Ferroelectric polymers have drawn tremendous attention in film capacitors owing to their high permittivity and ease of processing. Nevertheless, the energy density of such materials is severely constrained due to inferior breakdown strength. To address this dilemma, a double-gradient multilayered all-organic dielectric composite film is proposed, fabricated via a simple layer-by-layer solution-casting process. The experimental results demonstrate that the composite film significantly suppresses the leakage current compared to the pristine films, resulting in remarkable enhancement of the insulation properties. The finite element simulation results further reveal that the optimized electric field distribution induced by the gradient structure and the carrier traps at the interfaces between the adjacent layers play a crucial role in impeding the propagation of the breakdown path. As a result, the developed dielectric film reaches an unexpected breakdown strength of 712 MV m