The invention aims at providing a synthesis method of dodecanoxy phenyl porphyrin benzamide octane imine-perylene-decanilamine hexyloxy triphenylene ternary compound. The synthesis route is as follows: 10-amino decyloxy triphenylene is obtained from catechol as a raw material as a first part; hexyloxy triphenylene dibutyl methylenyl permide is synthesized from perylenetetracarboxylic dianhydride as the raw material as a second part; a porphyrin compound with an amino branched chain is synthesized as a third part; and intermediates obtained by the second part and the third part are subjected to amide reaction in imidazole to obtain a target compound as a fourth part. A ternary compound employing alkoxy porphyrin and alkoxy triphenylene as electron donors, a flexible alkoxy chain as a bridge body and a perylene diimide unit as an electron acceptor is designed and synthesized. The compound can be applied to the fields of an organic solar cell and an organic light-emitting diode.