In a ferroelectric liquid crystal display comprising a pair of transparent substrates each provided with a transparent electrode and an aligning film and a liquid crystal layer sandwiched between said substrates, the aligning film is subjected to a deionization treatment with, for example, an ion-exchange resin to reduce the total content of impurity ions in the aligning film of a polyimide resin or the like to 300 ppm or less, to reduce the total content of impurity cations to 200 ppm or less, to reduce the total content of Cl.sup.-, (COO.sub.2).sup.2- and CH.sub.3 COO.sup.- to 100 ppm or less and the content of each of these ions to 50 ppm or less, or to reduce the total content of PO.sub.4.sup.3-, NO.sub.3.sup.- and SO.sub.4.sup.2- to 100 ppm or less and the content of each of these ions to 50 ppm or less.