Background Geothermal resources is renewable energy with the characteristics of low-carbon, enormous reserves, widely distributed and recyclable. China leads the world in the direct utilization of geothermal energy for many years. Geothermal resource monitoring serves as the foundational work for the effective and secure operation of geothermal system. It provides critical data for understanding the dynamic changes in geothermal reservoirs and their surrounding geological environments. The result can also support to refined management and protection of geothermal resources.

Advances  (1) Geothermal resource monitoring can be divided into two categories. Narrow-scale monitoring is primarily applied to individual wells, whereas broad-scale monitoring is better suited for geothermal fields or geothermal systems. (2) The rapid development of monitoring technologies has enabled real-time monitoring of geothermal systems, providing important insights into system operation and facilitating early identification of potential risks. Relevant techniques include conventional parameter monitoring such as flow rate, temperature, pressure and liquid level, as well as seismic networks, geochemical analysis, gravity measurements, tracer tests, corrosion monitoring probes, and fiber optic sensing. (3) Countries such as the United States, France, and Iceland use long-term monitoring data to guide and adjust their geothermal development strategies. In China, monitoring networks have been established on an administrative basis, with cities including Beijing, Tianjin, and the Xiong’an New Area accumulating relatively mature experience. (4) Current challenges in the monitoring of shallow geothermal energy, hydrothermal resources, and hot dry rock resources include poor multi-source data sharing, insufficient spatial coverage, inadequate high-temperature resistance of downhole sensors, and the lack of unified information platforms and monitoring models.

Prospects  This paper proposes a “theoretical-technological- network” trinity framework for geothermal resource monitoring. Theoretically, it calls for establishing a fusion theory for heterogeneous multi-source data and a “geology-monitoring-geology” mutual feedback theory. Technologically, breakthroughs are needed in multi-dimensional collaborative monitoring (integrating space-ground-well platforms), intelligent service technologies based on artificial intelligence, and high-temperature-resistant monitoring equipment to achieve comprehensive spatial coverage and high-precision sensing. Network, it recommends implementing a three-tier Geothermal Resource Monitoring Network and National Ground Temperature Monitoring Network, consisting of national basic geothermal monitoring, geothermal field monitoring, and development/utilization project monitoring, supported by multi-stakeholder data sharing mechanisms. This integrated framework is expected to systematically address key challenges—including data silos and insufficient spatial coverage—while providing scientific and technological support for China’s energy revolution and the achievement of its carbon peak and carbon neutrality goals.