Abstract: Seismic T-waves are a type of solid-fluid coupled seismo-acoustic waves excited in the solid Earth (e.g., the crust and mantle) by marine events including earthquakes, volcanic eruptions, and submarine landslides, and converted through the dynamic interaction between the seabed and the water column. These T-waves are characterized by low energy attenuation during propagation and can travel over long distances in the ocean SOFAR (SOund Fixing And Ranging) channel, which acts as a low-velocity waveguide layer in the water column due to the temperature and pressure stratification of seawater. Therefore, T-waves are extensively applied in a set of research fields, including marine seismic monitoring, marine environment sensing, and offshore seismic safety assessment. In recent years, with the continuous accumulation of high-quality marine observation data from global marine observation networks and the better understanding of T-wave propagation mechanisms in complex solid-fluid media, the T-wave-related research has entered a new stage of development, bringing both opportunities and challenges. This paper systematically summarizes the recent research advancements regarding T-waves, in terms of observation technology, numerical simulation, and practical applications. In terms of observation, T-wave detection approaches have gradually evolved from early land-based seismic stations to a muti-dimensional observation system. This modern system is jointly composed of multiple advanced observation tools, including hydrophone arrays, Ocean Bottom Seismometers, Distributed Acoustic Sensing, and MERMAIDs (Mobile Earthquake Recorder in Marine Areas by Independent Divers), which have significantly improved the spatial coverage, temporal resolution, and signal-to-noise ratio of T-wave observations. In terms of simulations, multi-scale forward modeling frameworks have been established, covering ray theory, normal mode theory, and high-precision numerical simulation methods. These models have effectively revealed the complex excitation mechanisms of T-waves and their three-dimensional propagation characteristics under various complex bathymetry and solid earth structures. Besides, T-waves have been widely used in multiple research directions, including abyssal and open-ocean seismic monitoring, early warning of submarine volcanic activity, rapid tsunami assessment, long-term ocean temperature change measurement. These applications not only deepen the understanding of marine geological structures and seafloor deformation processes, but also enhance the capability of marine disaster response and marine environment sensing. In the future, studies of T-waves would focus on quantitative characterization of complex T-wave propagation characteristics, promoting the development of full-depth ocean observation technology to enhance the observability of abyssal oceans, introducing emerging technologies such as artificial intelligence to improve the efficiency and accuracy of T-wave signal processing and parameter inversion, and expanding the interdisciplinary application potential of T-waves in the study of ocean-solid Earth coupling processes. This paper aims to provide support and technical information for marine geoscience and geophysics research, as well as for disaster prevention and mitigation.