Now most software systems building in cloud computer platform use Multi - Tenancy architecture. A single software system serves multiple client organization. All customer data will be stored together in only one software system. So the systemneed higher can be equipped requirement of the data security. We want to build a data security monitoring mode used by on cloud platform large enterprises. The mode can set the authentication, logging, fine-grained access control, dynamic data filtering strategy, data audit in a body to realize the security protection of the enterprises data. In this paper themodel usesmulti-tenancy SaaS(Software as Service) applicationmode. It uses RBAC (Role-Based policiesAccess Control) mode and operation in the context of environmental perception to realize the data access control. It using PMI framework to provide accession management services for enterprise users.