Intramolecular pyrene excimers formed in three 1,3-dipyrenylpropanes with different pyrenyl ring substitution positions were studied by the transient absorption spectra of laser photolysis and by the emission decay analysis of single-photon-counting measurements. Time-resolved transient absorption spectra of 1,3-di(2-pyrenyl)propane (2Py2Py) and 1-(1-pyrenyl)-3-(2-pyrenyl)propane (1Py2Py) revealed the formation of full- and partial-overlap excimers, respectively. The full-overlap excimer of 2Py2Py has a sharp absorption band at 500 nm, whereas the partial-overlap type of 1Py2Py gave a broad band around 480-550 nm. The temperature dependence of the excimer emission intensity and decays gave the values of the excimer binding enthalpies. The full-overlap excimer of 2Py2Py gave a ca. 1 kcal/mol smaller binding enthalpy than the partial-overlap excimer of 1Py2Py due to the repulsive force of the pyrenyl rings.