This study aims to introduce the optical anisotropy and modulation characteristics of different liquid crystal materials in the terahertz (THz) regime. Herein, several THz functional devices were reviewed based on the combination of liquid crystals and artificial electromagnetic microstructures, realizing the functions, such as tunable filtering, electromagnetic induced transparency, phase modulation, and polarization control of THz waves. Moreover, the interaction mechanism between liquid crystals and artificial electromagnetic microstructures was analyzed and discussed, along with the regulation law of external field and surface interaction at the THz wavelength scale. In addition, the development trend in the applications of THz liquid crystal photonic devices was prospected.