To improve the comprehensive experimental skill of undergraduate and penetrate the concept of green chemistry education, we combined with the teaching needs of applied chemistry and designed a comprehensive experiment of preparing green drilling fluid treatment agent with waste citrus peel as raw material. Citrus fruit peel contains a lot of plant phenols, cellulose, soluble polysaccharides and other components, which can be used as drilling fluid to increase viscosity and reduce filtration loss. However, the proportion of water-soluble substance in citrus peel is low and the effect is poor. Therefore, to improve its utilization efficiency, we have applied different methods to modify the raw material, including the pretreatment, crosslinking, carboxymethylation to increase the proportion of water-soluble substance and improve its performance in drilling fluid. This experiment has introduced knowledge of organic chemistry to oilfield chemistry and combined experimental skills with field work, which will help to improve students' professional skills and field adaptability. In addition, using discarded citrus fruit peels as raw material in the experiment can practice the concept of green environmental protection, which is helpful to guide the future clean production of the oilfield and promote green and low-carbon development.