Abstract: Evaporation-enrichment method is an important part of the product preparation process, and is directly related to the yield and success of the experiment. In practice, students have insufficient ability to grasp the degree of enrichment, usually resulting in low yield or product, which leads to experiment failure. Therefore, the experiment design of potassium copper(II) oxalate complexes is used as an exploratory experiment. By exploring the relationship between concentrated volume and product, students' ability to control enrichment is improved, and students' experimental operation skills are improved, and students' ability to think independently is cultivated.