Abstract: With the continuous extension of resource development and underground engineering toward greater depths, the multi-field coupling mechanisms of deep rock masses and their associated disaster characteristics have become critical issues governing the safety and efficiency of resource extraction. To systematically investigate the response of deep rock masses under multi-field coupling conditions, a large-scale, transparent, multifunctional experimental system with a multi-field coupling environment was independently developed. The system consists of an environmental chamber, a temperature control module, a seepage (fluid flow) control module, a high-temperature-resistant acoustic emission monitoring and transparent wave velocity field imaging module, and a multi-channel data acquisition module. Moreover, it can be integrated with a large-scale three-direction five-surface rock testing platform. By independently or cooperatively simulating the in-situ stress, temperature, and seepage conditions of rock masses, the system enables multi-parameter monitoring of the response of relatively large-scale rock specimens under multi-field coupling conditions, and also achieves "transparent" dynamic observation and characterization of the entire process of internal damage and structural evolution within rock masses under multi-field coupling conditions. Specifically, the system supports real-time heating of rock specimens inside the environmental chamber and provides multiple temperature control modes, including constant-temperature, variable-temperature, and cyclic heating. Based on modular design of loading connectors and pads, various stress paths can be reproduced, such as uniaxial/biaxial compression, inclined shear, and horizontal shear. Through the seepage control module, fluid injection parameters can be precisely regulated to simulate localized fluid-rock interactions, thermo-hydro-mechanical coupling processes under high temperature and high pressure, and convective heat transfer during fluid flow. With the aid of this experimental system, uniaxial compression and biaxial loading tests with water injection and heat transfer under real-time heating conditions were conducted, verifying its feasibility. This proposed experimental system provides an effective experimental tool and technical foundation for in-depth investigations into deep rock mass stability, thermo-hydro-mechanical coupling mechanisms, optimization of geothermal extraction efficiency, and engineering risk control.