Osmotic swelling and reassembling behaviors of lithium taeniolite, Li(Mg2Li)Si4O10F2 (Li-TN), have been investigated by an in situ X-ray diffraction (XRD) technique under conditions where colloid concentration and drying speed were controlled. The 00l reflections observed were characterized by a wavy distribution of intensity along 2 theta without a flat region between the peaks. Profile analysis of the XRD pattern using Laue function indicated that the colloidal particle of Li-TN in dilute suspension consisted of a pair of the taeniolite sheets incorporating water. The peaks, 00l reflections of the colloidal Li-TN, shifted to lower angle with increasing water concentration and to higher in the drying process. The swelling and reassembling processes are discussed on the basis of the present model of the unit particle in suspension.