Improper treatment of herbicides can cause soil, water and air pollution, and will enter the food chain through the environment, which will affect human health. Atrazine, as a common herbicide, is often detected in the water environment around the world. At present, the main detection methods mainly depend on large instruments, which usually need complex pretreatment, and the skill requirements of operators are high, which is difficult to popularize. With the development of optical materials, terahertz has been expanded to more and more fields, and it is often used to identify the subtle changes of materials. The transmission spectrum of atrazine solution (0, 1, 10, 100, 1000, 2000 ug/L) was detected by terahertz spectroscopy and ultra-material. The transmission spectrum was normalized and analyzed by fitting. The experimental results show that the concentration of atrazine in the range of 1-2124 ug/L can be detected accurately by using terahertz spectroscopy and the super materials, which can effectively improve the sensitivity of pesticide detection.