This essay mainly discussed the impact of China's "Double Reduction" policy on students from the perspective of educational ecosystem theory. The "Double Reduction" policy aims to reduce students' excessive homework burden and the burden of out-of-school training, so as to alleviate students' pressure. This paper first introduces the concepts of educational ecosystem theory, such as microsystem, mesosystem and exosystem. It then discusses how the "Double Reduction" policy has changed the educational ecosystem, especially at the macrosystem level. The paper also discusses how the implementation of the "double-decrease" policy affects students through various system levels. In general, the "double-decrease" policy has helped to reduce the pressure on students' development, but it has also brought uncertainty to academic performance and career development. This paper adopts a qualitative research methodology by interviewing students and parents to explore their attitudes towards the "double-decrease" policy and its perceived impacts. It also concludes that if China's unique education system does not change accordingly, the effects of the double-minus policy will be greatly weakened by society, and the long-term impact will be more uncertain.