The invention discloses a synthesis method of benzophenanthrene decyloxy bridged isooctyl alkoxy phenyl porphyrin ternary compound disc-like liquid crystal material. The synthesis method comprises the following steps: firstly, performing synthesis to obtain dipyrrole and bi-isooctyl alkoxy benzaldehyde respectively, then performing synthesis on the dipyrrole and the bi-isooctyl alkoxy benzaldehyde to obtain porphyrinate, so that porphyrin acid is obtained; secondly, generating single hydroxyl-penta-hexyloxy benzophenanthrene, then performing synthesis to obtain alkoxy benzophenanthrene with an omega-bromine branched chain; thirdly, performing synthesis on the intermediates obtained in the above steps to obtain a benzophenanthrene decyloxy bridged isooctyl alkoxy phenyl porphyrin ternary compound. Synthetic raw materials of a benzophenanthrene ramification are easy to get, and a product is easy to refine, and has good optical property and heat stability; a synthesis method of a porphyrin derivative is mature, and has good fluorescene and aromaticity. The benzophenanthrene decyloxy bridged isooctyl alkoxy phenyl porphyrin ternary compound disc-like liquid crystal material can be applied to molecule devices such as organic solar cells, organic photovoltaic materials, liquid crystal materials and the like.