An aromatic polymer, containing a repeating unit represented by Formula (I), and having properties (A1) and (B1): (A1) the number average degree of polymerization of an acetylated product obtained by acetylation of the hydroxyl groups of the polymer is 3 or more, and (B1) at a wavelength where an absolute value of molar ellipticity (degreecm.sup.-2dmol.sup.-1) per mole of the repeating unit of the acetylated product in a circular dichroism spectrum of the acetylated product reaches maximum in a wavelength range of from 200 to 350 nm, the absolute value is 50,000 or more: ##STR00001## wherein R represents a hydrocarbon, hydrocarbon-oxy, hydrocarbon-mercapto or hydrocarbon-amino group that may be substituted; the two R's may bind to each other to form a ring; and the repeating unit represented by Formula (I) has no symmetrical plane that has two binding sites and that is perpendicular for the benzene ring.