As society develops, the need to store and use data is increasing, meeting data on the cloud is not enough, so we need more data to be shared outside. A cloud outsourcing data sharing technology based on linear geometric level key management is proposed to solve the full sharing of existing cloud outsourcing data and complex hierarchical structure and access groups. Hierarchical Key Management technical diagram and principles are explained, and three rules are designed. The article will design and analyze in detail the system construction algorithm, key derivation algorithm and dynamic key management. The algorithm is tested experimentally, and the verification results show that the solution is safe and relatively effective.