In response to the common problems of low success rate, poor reproducibility, and poor product shape in the preparation experiment of copper ammonia fiber, based on the competitive mechanism between sulfate ions (SO42-) and cellulose during the dissolution process of defatted cotton, this study explores the effects of SO42- concentration and defatted cotton dosage on the experiment. The results showed that for about 0.01 mol of copper element, controlling the SO42- mole fraction below 20% can improve the success rate and reproducibility of the experiment. High quality fibers can be obtained when the amount of defatted cotton is 0.5 g. Using Cu(OH)2 solid instead of CuSO4 solution to prepare copper ammonia fibers can significantly improve the success rate. And design an exploratory experimental plan, designing this process as a high school chemistry experiment, which can enhance students' experimental skills and stimulate their enthusiasm for scientific research.