Flexible films having high dielectric constants with low dielectric loss have promising application in the emerging area of high‐energy‐density materials. Here, for the first time, an organometallic, Sn‐polyester‐containing hybrid free‐standing film in polyimide matrix is reported. Polyimide, pBTDA‐HDA, is used with poly(dimethyltin glutarate) and poly(dimethyltin‐3,3‐dimethyglutarate) (pDMTDMG) for having a processable film with tunable dielectric properties. Hybrid film with 60% pDMTDMG and 40% PI (HB2) is found to have improved dielectric features over previously synthesized organic polyimide and organometallic Sn‐polyester homopolymers. These novel organometallic–organic hybrid systems expanded a new area of dielectrics for next‐generation electronics with superior overall electrical performance.