Two new coumarin derivatives containing phenothiazine or phenoxazine moiety, 3-(benzo[d]oxazol-2-yl)-7-(10H-phenoxazin-10-yl)coumarin (PXZ-C) and 3-(benzo[d]oxazol-2-yl)-7-(10H-phenothiazin-10-yl)coumarin (PTZ-C), were synthesized and characterized by elemental analysis, NMR spectroscopy, and MS. Their photophysical and electrochemical properties and thermal stabilities were investigated systematically. The results showed that these compounds have good thermal stability. The compound PTZ-C exhibits weak blue–green emission upon ultraviolet light excitation, whereas the compound PXZ-C displays weak blue emission.