Liquid crystal polyester fibers containing a liquid crystal polyester, in which the liquid crystal polyester has a repeating unit represented by Formula (1), a repeating unit represented by Formula (2), and a repeating unit represented by Formula (3), at least one repeating unit selected from the group consisting of the repeating unit represented by Formula (1), the repeating unit represented by Formula (2), and the repeating unit represented by Formula (3) contains a 2,6-naphthylene group, a content of the repeating unit containing the 2,6-naphthylene group is 40 mol % or greater with respect to a total content of all the repeating units of the liquid crystal polyester, and an orientation degree of the liquid crystal polyester in a length direction of the fiber is 89% to 95%. (1) —O—Ar1—CO—, (2) —CO—Ar2—CO—, and (3) —X—Ar3—Y—, wherein Ar1 represents a phenylene group, a naphthylene group, or a biphenylylene group, Ar2 and Ar3 each independently represent a phenylene group, a naphthylene group, or a biphenylylene group, and at least one selected from the group consisting of Ar1, Ar2, and Ar3 contains a 2,6-naphthylene group. X and Y each independently represent an oxygen atom or an imino group (—NH—). Hydrogen atoms of the group represented by Ar1, Ar2, or Ar3 may be each independently substituted with a halogen atom, an alkyl group having 1 to 10 carbon atoms, or an aryl group having 6 to 20 carbon atoms.