Techniques for data source driven expected network policy control are described. A policy enforcement service receives, from a compute instance in a virtual network implemented within a service provider system, a request to access data. The policy enforcement service determines that a virtual network security condition of a policy statement is not satisfied. The policy statement was configured by a user for use in controlling access to the data. The virtual network security condition defines a condition of the virtual network that is to be met. The policy enforcement service performs one or more security actions in response to the determination that the virtual network security condition of the policy statement is not satisfied.