Spectroscopic and Photoelectric Characteristics in the Cyanine and Merocyanine Dye according to systematically change of their structures were experimentally discussed. As result, in solution, Hetero atoms(X) of Cyanine and Merocyanine dye were participated in resonance X of d obital rather than X of pobital,effected in resonance and contributed in extension of conjugated system. in solid film,new spectra,called eximer-fluorenscence,were appeared in 3-dimensional fluorenscence of high density of Cyanine dye but not of Merocyanine. The activational energy of conductivity in Merocyanine dye was lower than in cyanine, an the contrary,the drift mobility was higher and the former in photoelectric characteristics was more effec-tive than the latter. In this paper,authors invertigated the changes of dye structure by molecular obital method to confirm the results of spectroscopic and photoelectric characteristics in the Cyanine and Merocyanine Dye acco-rding to systematically cally change of their structure, and counted total energy on dihedral angle and dipol miments if dyes in S0 and S1.