We　demonstrate　a　remarkable　integration　of　metallacycles　and　polyoxometalate　(POM)　macrocycles　at　the　molecular　level,　forming　a　series　of　unprecedented　organic-inorganic　hybrid　POM-metallacycle　composite　macrocycles　with　interesting　bi-layer　and　tri-layer　cyclic　structures,　as　well　various　compositions,　nuclearities,　geometries,　and　sizes.　These　molecular　composite　macrocycles　show　a　fusion　of　metallacycle　and　POM　chemistry,　which　opens　new　perspectives　for　developing　brand-new　ring-shaped　composite　materials.　©　the　Partner　Organisations.