In order to explore the photoelectric properties of the fuse ring compound 3- phenyl-6-(4-methylphenyl)- 1,2,4-triazolo [4,3-b]- 1,2,4-triazine, the compound crystal structure had been computed by Gaussian program, its properties were studied with density functional theory B3LYP method using 6-31G(d) basis set, and the stably geometric configuration and bond length,bond angle are obtained and accorded with the experimental value. The properties of the title compounds attaching different substituent to 6-position phenyl have been discussed through the transfer of electric charge, energy level of the frontier molecular orbit and the emission spectrum and so on.The emission wavelength of the compounds attaching different substituent is in 512 ～521 nm, and the photoelectric properties of the compounds with different substituent were analyzed. Different substituent operates on the related compound by inductive and conjugative effect,and meanwhile the properties were affected by altering transferred electric charge number.These fuse ring compounds can be used as photoelectric materials based on computed result.