Modern biomedical imaging has revolutionized life science by providing anatomical, functional, and molecular information of biological species with high spatial resolution, deep penetration, enhanced temporal responsiveness, and improved chemical specificity. In recent years, these imaging techniques have been increasingly tailored for characterizing biomaterials and probing their interactions with biological tissues. This in turn has spurred substantial advances in engineering material properties to accommodate different imaging modalities that was previously unattainable. Here, we review advances in engineering both imaging modalities and material properties with improved contrast, providing a timely practical guide to better assess biomaterial-tissue interactions both in vitro and in vivo.