(Task) It is possible to form a liquid crystal alignment film with excellent reliability, which does not reduce the voltage retention rate over a long period of time and does not cause afterimages even under severe use conditions, and provides a liquid crystal aligning agent with excellent coating properties (printability). To provide.
(Solution means) It is a liquid crystal aligning agent containing polyarylene. The polyarylene is preferably a polymer having a repeating unit represented by the following formula (P):

(In formula (P), Ar is an n+2-valent aromatic group, n is 1 or 2, and X is a single bond, an oxygen atom, a sulfur atom, a carbonyl group, an ester bond, a thioester bond, -NR- or -CONR. -(R is a hydrogen atom or an alkyl group of 1 to 6 carbon atoms), and R ⁰¹ is a hydrogen atom, a hydroxyl group, a group having a terminal C=C double bond, a group having a triple bond between carbons, a group having an epoxy group, Selected from a group having a function of aligning liquid crystal molecules and a group generating a crosslinking reaction or an isomerization reaction by light irradiation).