Abstract: | The self‐assembly process of a Pd12L24 sphere was revealed by a quantitative approach (quantitative analysis of self‐assembly process: QASAP) quantifying all the substrates, the products, and the observable intermediates, indicating that the Pd12L24 sphere is produced through several pathways. Firstly, Pdn L2n (n= 6, 8, and 9), which are perfectly closed structures smaller than the Pd12L24 sphere, and a mixture of intermediates not observed by NMR ( Int ) were produced. Next, the sphere was assembled from intra‐/intermolecular reaction of a certain class of Int (path A) and from the coordination of free pyridyl groups in Int to the PdII center of Pdn L2n (n= 6, 8, and 9) (path B). While capping the free pyridyl groups in Int with PdII ions perfectly inhibited the sphere formation, the addition of free L to Int accelerated the formation of the sphere. |