Non-covalent conformational locks (NCLs) such as S··N, Se··O, and S··O are effective strategies to improve the planarity and stiffness and charge mobility of organic/polymer semiconductor materials. Therefore, by introducing S··Cl NCLs, the planarity and rigidity of the π-conjugated skeleton of the small molecule acceptor ITCIC molecule are improved, thereby enhancing the charge mobility. As a result, the PCE of PM6:ITMIC-based organic solar cells reached 11.34% compared to PM6:ITMIC-based organic solar cells. This paper demonstrates that a new type of S…Cl NCLs can improve the photoelectric conversion efficiency of organic solar cells.