Multispectral image fusion, integrating X-ray, visible, and near-infrared (NIR) signals, is revolutionizing the acquisition of comprehensive structural information. However, conventional multi-detector systems suffer from pixel misalignment and complex integration, limiting practical applications. Herein, switchable radiative recombination is achieved in a single (ATPP)2ZnCl4:Sb3+ (ATPP = acetonyltriphenylphosphonium) crystal through Sb3+ doping, and this can be applied to multispectral image fusion. Notably, the coexistence of singlet and triplet self-trapped excitons induced by the dopant creates distinct radiative pathways, thereby enabling excitation-dependent luminescence switching between visible and NIR emission, in combination with efficient X-ray responsiveness. Consequently, under 330 nm excitation, the optimized material exhibits ultrabroad warm white emission with a near-unity photoluminescence quantum yield (PLQY) of 95.3%. Significantly, the potentially harmful blue-violet component is suppressed to a record-low 7.5%, which ranks among the lowest values reported for single-component white-light emitters. Interestingly, when the excitation is switched to 365 nm, efficient NIR luminescence peaking at 690 nm (PLQY > 60%) is activated, and the crystal simultaneously serves as an effective scintillator for X-ray imaging. Leveraging these versatile multimodal characteristics, we have successfully realized depth-resolved fusion imaging of complex encapsulated structures.