As an artificial composite material with extraordinary physical properties, metamaterials can break through the limitations of conventional materials and open up a new way to design advanced functional materials. Terahertz waves have the characteristics of low photon energy, no ionization damage to biological substances, and molecular fingerprints etc. By combining with metamaterials, high-sensitivity detection of biological substances can be achieved, and it has attracted more and more attention from scholars at home and abroad. This article summarizes the progress made by terahertz metamaterial sensors in the field of biomolecule and cell detection in recent years. Firstly, the sensing principle and performance indices of the terahertz metamaterial sensors are introduced. Secondly, the development of the terahertz metamaterial sensors in the field of biological detection is described from the aspects of metamaterial structure design, substrate selection, and combination with microfluidics and new materials. The sensitivity of the metamaterial sensors can be further improved by optimizing the structure of the metamaterial, using a thin substrate with low dielectric constant, combining microfluidic technology or attaching a new material coating to the sensor, and their functions in biomedical detection can be enriched. Finally, the development trend and prospect of terahertz metamaterial sensors are envisioned.