To provide a liquid crystal aligning agent useful to obtain a liquid crystal alignment film excellent in liquid crystal alignment properties, alignment controlling power and rubbing resistance, having high voltage retention characteristics and having reduced charge accumulation, and a liquid crystal display device which is less susceptible to display failure, to lowering of contrast or to image persistence.A liquid crystal aligning agent comprising a low resistance polyimide precursor having a volume resistivity of from 1×1010 to 1×1014 Ωcm when formed into a film, and a high alignment polyimide precursor or polyimide having a specific structure, and a liquid crystal display device employing this liquid crystal aligning agent.