To investigate the photophysical properties of intramolecular charge transfer mechanism, three boron-dipyrromethene derivatives with different bulk sizes of polyaromatic hydrocarbon at meso-position have been synthesized and fully characterized. The thermodynamics test results revealed that the triphenylene meso-substituted-boron-dipyrromethene possesses the highest thermal stability comparing with the boron-dipyrromethene compounds which meso-position has been substituted by triphenylamine or tetraphenylethylene. The thermal decomposition temperature and melting point of triphenylene meso-substituted-boron-dipyrromethene are up to 369 degrees C and 297 degrees C, respectively. The UV-Vis absorption spectra, fluorescence emission spectra and quantum chemical calculations indicated the significant intramolecular charge transfer characteristic from Donor (triphenylene) to Acceptor (BODIPY) moiety.