Highly ordered nanostructures of liquid-crystal molecules were patterned within porous anodic alumina of different pore diameters. As the utilized pore diameter of the porous membrane decreases, progressively red-shifted emissions are observed for the embedded liquid-crystal nanostructures at room temperature. This unique spectral progression, depending on the pore size, is very similar to the emission trend induced by the thermotropic phase-transitions of the bulk antiferroelectric liquid-crystal. Such characteristics are considered to be due to structural confinement of the antiferroelectric liquid-crystal molecules within the finite size of nanoporous channels.