The strain effects on the electronic structures of La0.67Ca0.33MnO3 (LCMO) and La0.8Ba0.2MnO3 (LBMO) thin films have been studied by O K-edge x-ray absorption near edge structure (XANES) spectroscopy. For LCMO, the first-principles calculations reveal that the features in the XANES spectra are associated with hybridized states between O 2p and Mn minority-spin 3d t2g and eg, La 5d∕Ca 3d, and Mn 4s∕Ca 4p states. An analysis of these features shows that the tensile strain decreases substantially La–O and Ca–O hybridization and TC for LCMO. For LBMO, the small compressive strain enhances slightly La–O and Ba–O hybridization and TC.