An acetylene-based polymer, comprising n recurring units represented by the following Formula (1): CH═CAn  (1) wherein, n is an integer of 10 to 10,000; each A represents a group selected from a naphthyl group, a phenanthryl group, a pyrenyl group and an anthryl group, which is mono- or di-substituted with a group selected from alkyl groups, alkyl groups substituted with aromatic hydrocarbon groups, R1—O— groups, —S—R2 groups, —NR3R4 groups, a cyano group, a carboxyl group, R5SO2— groups, —COOR6 groups, —CON(R7)(R8) groups and —COR9 groups (each of R1, R5, R6 and R9 is an alkyl group, each of R2, R3, R4, R7 and R8 is a hydrogen atom or an alkyl group); and the recurring units may be the same as or different from each other.