A diaminodicyanopyrazine derivative, having bulky substituents, was designed and synthesized. The synthesized dye exhibited an intense photoluminescence in the solid state. An electroluminescent device was prepared by using the dye. The dye exhibited polymorphism. Red and yellow single crystals of the dye were prepared by using a gas-phase sublimation growth procedure. The spectral shift due to the polymorphism is also discussed, and a candidate dye for red colored electroluminescent devices is proposed.