Abstract: Cloudlet, which can perform resource-intensive applications for users with low delay, is a small data center located at the edge of the Internet. Compared to virtual machine technology, container technology has become the first choice to build a cloudlet due to its higher resource use rate, physical-machine-like performance and faster boot speed. The monitoring system is indispensable to the operation of a cloudlet. Combining the maturity framework of existing monitoring systems and the characteristics of container-based cloudlet, a monitoring system was designed and implemented for container-based cloudlets. And the monitoring system realizes the collection, storage, aggregating and displaying of monitoring data, anomaly detection, and dynamic settings of thresholds and collection cycles. At the same time, a request aggregating algorithm was proposed to reduce. Actual deployment and testing indicate that the system can meet the design requirements with low load.