In this study, we report a new kind of chiral hybrid material which was prepared through three-dimensional (3D) assembly of silver nanoparticles (Ag NPs) into a 3D blue-phase (BP) polymer nanostructure template by in situ reduction of silver nitrate. A feature signal at plasmonic wavelengths of Ag NPs could be found in the circular dichroism spectra after assembly of Ag NPs within the 3D BP template due to the localized surface plasmon resonance of Ag NPs. Additionally, the chiral hybrid material not only shows a sensitive response to different amounts of Ag NPs but also exhibits pronounced sensitivity to different surrounding dielectric environments. These kinds of chiroptical hybrid materials can be valuable in a wide range of applications such as refractive sensing, protein inspection and other biomedical fields.