The thermal decomposition behavior of Sr(DPM)(2) (DPM: 2,2,6,6-tetramethyl-3,5-heptadionate, C11H19O2) was studied using thermogravimetry, mass, UV, and in situ infrared spectroscopy. In particular. dissociation of the chemical bonds in the complex ligand has been studied by monitoring the change in the intensity of the IR peaks while the sample is heated. The decomposition behavior of Sr(DPM)(2) is sensitive to the ambient gases and the Sr complex is severely degraded after storage for a year, The chemical bonds in the complex begin to be dissociated at low temperatures and are sequentially decomposed at elevated temperatures. The Sr-O and the C-C(CH3)(3) bonds dissociate most easily. then the C-H bond. while the C-O and the C-C bands are stable up to high temperatures. Decomposition of the Sr complex is enhanced when it is exposed to O-2 because removal of the tert-butyl. group from the ligand skeleton facilitates the Sr-O bond dissociation. Compared with the Ti-O bond in Ti(O-iPr)(2)(DPM)(2), the Sr-O bond is easily dissociated due to its ionic bond character as confirmed by UV spectroscopy. Removal of the tert-butyl group and dissociation of the Sr-O bond trigger oligomerization of the Sr compound so that a large amount of carbonate residue is obtained at high temperatures.