The spectral properties of the films based on optically transparent polymer materials with different polarity (polystyrene, polycarbonate) doped with dimethylaminostyryl β-diketonates of boron difluoride were studied. The transition from the less polar PS matrix to the more polar PC matrix leads to a solvatochromic effect due to internal charge transfer. The existence of two emitting centers in the polymer compositions was revealed: the monomeric luminescence and the luminescence of aggregates. The ratio between numbers of the emitting centers depends on the method of the film formation. Luminescence of polymer films doped with β-diketonates of boron difluoride has higher quantum yield than luminescence of solutions due to the formation of aggregates. The registration method has a significant effect on the structure of the steady-state luminescence spectra of the films. The substrate effect can be used to intensify the short-lived emission process.