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In nature, animals employ tunable structural colors for communication or camouflage through iridophores, which act as biological “pixel” units. Inspired by the cellular architecture of iridophores, this study introduced a rapid and straightforward process for fabricating microspheres with tunable structural color through the aggregation of poly(N-isopropylacrylamide-2-aminoethyl methacrylate hydrochloride) (PNIPAM-AEMA) nanogels. Unlike previous methods in which microspheres were obtained by physical attraction between the nanoparticles, the microspheres here were stabilized by cross-linking between nanogels. The microspheres were obtained by dripping a PNIPAM-AEMA nanogel emulsion containing glutaraldehyde into silicone oil to form spherical droplets. As water evaporated, the nanogels were concentrated and underwent cross-linking via glutaraldehyde, yielding PNIPAM-AEMA nanogel-based microspheres. When hydrated, these microspheres displayed dynamically tunable structural colors through temperature-dependent modulation of the PNIPAM-AEMA nanogel dimensions. Moreover, the resulting microspheres displayed an angle-independent structural color for the short-range ordered nanogels. Furthermore, bioinspired skin with spatially patterned and dynamically tunable colors could be engineered by integrating microspheres that contain PNIPAM-AEMA nanogels of different sizes. Such microspheres, possessing a tunable and reversible structural color, may offer potential applications in chemical/biological sensing, displays, encoding, and optical switching.