Network monitoring systems are designed to fulfill operators’ intents and serve as essential tools to modern networks. As a result of rapidly increasing network bandwidth and scale nowadays, network monitors should satisfy on-demand network monitoring for continuously growing traffic volumes. However, existing monitoring systems either cannot satisfy flexible intents on demand or produce significant overheads. In this paper, we present Newton, an intent-driven traffic monitor that is able to specify operators’ intents with traffic monitoring queries and conduct dynamic and scalable network-wide queries deployment. Newton enables operators to customize and modify queries dynamically without interrupting the network workflow. Besides, Newton proposes systematic optimizations at device level and network-wide level to reduce resource consumption while deploying queries. Newton can combine the resources across switches to deploy complex queries with high resilience to dynamic network status. Evaluations prove that Newton is of high flexibility, scalability, and resource efficiency, which demonstrates Newton is promising to be deployed in large-scale programmable networks.