Terahertz time-domain spectroscopy （THz-TDS）, as an emerging detection technology developed rapidly in recent years, has been widely used in the agriculture, chemical industry, pharmacy, and other detection fields due to its powerful perspectivity, high security, and efficient spectral resolution. In this paper, we introduced the recent research status of terahertz spectroscopy in the detection of inferior agricultural products, the detection of pesticide residues, the detection of banned additives, the identification of genetically modified crops, and the detection of moisture content in agricultural products. Furthermore, we summarized the main technical problems of terahertz spectroscopy in the detection of agricultural products and forecasted the development prospects of this technology. As science and technology develop forwards, terahertz spectroscopy will have more bright application prospects in the future.