HLS-II is a dedicated synchrotron radiation source mainly based on vacuum ultraviolet and soft X-rays. As a user facility, it has high requirements for operating performance. To improve the real-time performance and convenience of data query and meet the needs of staff to keep abreast of the operation status of the facility in time, the HLS-II mobile data query system is developed based on Web technology. The system is developed in the EPICS environment. IOC is used as the real-time data source, HBase database as the historical data source, Phoebus Alarms as the alarm data source, and MySQL database is used to store the user management information. The whole system adopts the design pattern of separation of front and back ends. The back end of the system is developed with Spring Boot framework and Node.js environment. The front end of the system is developed with the Vue.js framework, using lib-flexible layout scheme and postcss-pxtorem plug-in to adapt to different types of mobile devices. The test results show that the HLS-II mobile data query system can update information smoothly, operate intuitively and conveniently, and meet the design requirements.