The relationship between crystallographic and helimagnetic chirality has been paid attention, because the sense of a screw spin structure depends on the right- or left-handed chiral crystal structure that allows a Dzyaloshinskii-Moriya (DM) interaction. CsCuCl3 is a very good candidate because it has a chiral crystal structure with a space group of P6122 and shows helimagnetism below 10.5 K. Some experimental groups have performed polarized neutron diffraction experiments. However, they got inconsistent results, because of difficulties in evaluating and controlling the crystallographic chirality. By our unique crystallization and X-ray diffraction technique, we recently succeeded in obtaining mm-ordered single crystals with well-controlled crystallographic chirality. In order to solve the disagreements in the past neutron studies and to investigate the interplay between crystalline and magnetic chirality, it is strongly necessary to perform new polarized neutron diffraction experiments in CsCuCl3. For that reason, we are applying for 7 days of beam time in D23 instrument