Significance The striking colors of organisms, like butterflies, have sparked tremendous research interest in developing artificial photonic crystals with extraordinary optical properties. In most cases, the color of photonic crystals originates from the periodic microstructure that manipulates light through optical interference. Here, we report a photonic structure that does not rely on long-range periodic arrangements. Instead, such structural color comes from the nematic liquid crystals of nanodiscs as opposed to the conventional achiral nematic phases that are colorless under white light. This finding challenges the stereotypical design of photonic liquid crystals based mainly on periodically layered or helical structures. We expect that the concept of nematic photonic nanoparticles may open research opportunities for developing advanced photonic materials.