Grotto temples are invaluable cultural heritage and crucial physical resources for studying the history of Buddhism and ancient sculptural art in China. However, they are susceptible to natural environmental factors like weathering and erosion, which can lead to the development of joints, fractures, and karst cavities in the rock of the grotto ceilings. These geological issues can cause water leakage and structural instability, threatening the long-term preservation of the caves and their wall sculptures. To tackle these challenges, we employed a combined approach using ground-coupled shielded antennas with center frequencies of 400 MHz and 270 MHz. This method utilizes a grid layout for comprehensive non-destructive detection of concealed geological structures in the ceiling of a specific grotto temple. The collected Ground Penetrating Radar (GPR) data from the grid lines were then analyzed using three-dimensional (3D) visualization techniques. The results reveal that the integrated use of 400 MHz and 270 MHz antennas not only allows for the detailed delineation of geological anomalies, such as lithological interfaces, fractures, and karst cavities within the cave ceilings, but also clearly outlines the topographic relief of the rock mass. Furthermore, the 3D visualization of the GPR data enables viewing and analyzing the 3D radar data volume from various angles and dimensions, providing an intuitive representation of the rock structure, anomalies, and other relevant information. This significantly enhances the efficiency and accuracy of data interpretation. The application of GPR non-destructive detection technology is highly beneficial for analyzing the geological causes and pathways of water leakage in grotto temples. It provides an important basis for water hazard management, cultural relic preservation, and reinforcement efforts.