Biomineralization brings inorganic materials into biological organisms and it plays an important role in natural evolution. Inspired by biomineralized eggs and diatoms with protective shell structures, scientists have artificially endowed organisms with functional materials. The resulting organism-material hybrids become more robust and even evolve new functions. This feature article reviews recent achievements of organism improvements by various material shells and related applications in cell protection, storage, thermal stability, biological stealth, photosynthesis and biocatalysis, etc. Different from the previous understanding of biomineralization, the regulation effects of materials on organism functions are highlighted in these biomineralization-inspired biological improvements, which present an artificial evolution strategy by using material techniques. We suggest that rationally designed organism-materials with optimized functions can shed light on solving global problems such as energy crisis and environmental pollution, as well as on improving medical treatment and intricate material designing. More generally, the studies of material-based organism improvement can combine biological and material sciences together for a closer integration.