General Secretary Xi Jinping proposed: "Actively respond to the aging of the population, and build a policy system and social environment for the elderly, filial piety and respect for the elderly." The low birthrate and aging caused by low fertility rate have become common problems faced by countries around the world. In November 2020, the results of the seventh national population census were released. Based on the results of the seventh population census and the data released by the leading group of the seventh population census, this project aims at the low fertility rate reflected in the data, relies on the hot big data technology in the current era to analyze the reasons, combines online data literature review and offline questionnaire survey, investigates its formation process, and the possible subsequent impact.