The synthesis of two new 2,4-diaryl-1,3-selenazoles series were achieved by subjecting primary arylselenocarboxylic amides to cyclization with α-bromoketones. The systematic preparation of 2,4-diaryl-1,3-selenazoles was carried out by the primary selenoamides with α-halo ketones. Selenoamides were obtained from the reaction of NaHSe with aryl nitrile .The resulting 2,4-diary-1,3-selenazoles have been characterized by different spectroscopic methods; such as 1H ,13C NMR, IR, and mass spectroscopic data to prove the structural formula of the prepared compounds. Theoretical study has been carried out by using DFT theory to study the structural and electronic properties of prepared compounds.