Abstract: Strengthening the intervention of myopia in children and adolescents is an important measure to deal with the population shortage and promote the long-term balanced development of the population.At present, the rate of children's myopia is rising in China, and the low age and severe myopia are becoming more and more serious.As a human capital investment strategy for families in the era of fewer children, out-of-school training education exists in the context of the "double reduction" policy, which affects children's daily learning and lifetime arrangement, and then affects their vision health.Based on the whole school questionnaire survey data and physical health monitoring data of Y primary school in Hangzhou, this study analyzes the influencing factors of pupils' vision changes, and clarifies the impact path of attending out-of-school training education on vision health by using OLS regression model, intermediary effect model and adjustment model.The research found that after-school training education had a negative impact on visual changes by squeezing outdoor sports and sleep time, and parent-child companionship could effectively adjust the above negative effects.Therefore, in the process of promoting the effective implementation of the "double reduction" policy and the intervention of children's myopia, we should pay attention to giving guidance to the reasonable allocation of primary school students' learning, outdoor activities and sleep time, and pay attention to the role of parent-child companionship.

Key words: outside school training education, visual health, children