We have developed a simple and straightforward synthesis of chiral spiro-imidazolidinone cyclohexenones, featuring six contiguous stereocenters, from feedstock chemicals such as aminophenols, α,β-unsaturated aldehydes, and α-amino acids. Remarkably, this one-pot multicomponent reaction exhibits exceptional diastereoselectivity (>20:1 dr) and relies solely on an amino acid precursor as the chiral source, avoiding the use of transition metals or additional organocatalysts. This reaction is efficient and scalable, enabling synthesis on a gram-scale.