A method for producing a high-molecular weight liquid crystal compound, the method comprising a step of copolymerizing a monofunctional monomer and a polyfunctional monomer to obtain a high-molecular weight liquid crystal compound,
- wherein a content of the monofunctional monomer is 90% by mass or more with respect to a content of all monomers that are used for polymerizing the high-molecular weight liquid crystal compound,
- wherein a content of the polyfunctional monomer is 10% by mass or less with respect to the content of all the monomers that are used for polymerizing the high-molecular weight liquid crystal compound,
- wherein the monofunctional monomer contains a mesogenic group.