Circularly polarized luminescence (CPL) has received much attention in optical displays, information storage, and biological probes. Designing effective strategy to improve the CPL activities is significant for complex materials. Structural modification is a rational way which is seldom reported. In this work, three chiral binuclear Eu(III) complexes coordinated with different chiral Schiff base ligands were designed and synthesized. CPL performances of these Eu(III) complexes were substantially improved by polarity of substituents at the chiral carbon sites of the ligands, leading to a five-fold increase in the luminescence dissymmetry factor (glum). Additionally, three complexes exhibited similar luminescence properties with the characteristic peaks of Eu(III) ion, which can be rapidly quenched by Co(II) ion, allowing their further applications in anti-counterfeiting and sensors. Therefore, this work not only uncovers the relationship between the substituents of chiral ligand and the corresponding CPL properties of Eu(III) complexes to some extent, but also creates opportunities for design and synthesis of Eu(III) complexes with excellent CPL activity.