The invention discloses a terahertz metamaterial unit structure and a preparation, adjusting and control method thereof and relates to the technical field of metamaterials and terahertz detection. The terahertz metamaterial unit structure is composed of a bottom layer, a middle medium layer and a surface layer, wherein the bottom layer is a layer of continuous metal film, the middle medium layer is one of a polyimide film, a silicon nitride film, a silicon oxide film, an amorphous silicon film, a silicon oxynitride film, an aluminum oxide film, a hafnium oxide film and an aluminum and hafnium oxide film, and the surface layer is a surface resonator, and the surface resonator is graphical metal with the interior in an H shape and the periphery of a framework structure. According to the adjusting and control method of the terahertz response characteristic of the metamaterial, the whole metamaterial unit structure meeting impedance matching requirements can be decreased or amplified proportionally, and the terahertz absorption frequency and the response frequency band of the metamaterial can be adjusted within an ideal range. The terahertz metamaterial unit structure has the advantages of being simple in structure, easy to integrate, and capable of being applied to terahertz detectors.