Abstract: Internal Solitary Waves (ISWs) are a type of strongly nonlinear submesoscale processes occurring in the stratified ocean interior, which play an indispensable role in ocean mixing, energy cascade, material transport, and marine engineering safety. Due to their rapid evolution and complex spatial structures, continuous observation and dynamic analysis of internal solitary waves remain major challenges in remote sensing. Therefore, the development of effective observation technologies for internal solitary waves is of great significance for both scientific research and operational applications. In recent years, geostationary optical satellites, represented by Himawari-8/9, FY-4A/B/C, and GK-2A, have enabled minute-level high-frequency observations of ISWs. Meanwhile, radar altimetry has experienced three generations of technological development, overcoming the limitation of traditional optical and SAR techniques that only capture two-dimensional sea surface roughness, and providing important support for observing sea surface height modulations induced by ISWs. Based on recent studies, this paper systematically reviews the advances in the observation of ISWs using geostationary satellites and radar altimeters from the perspectives of temporal evolution and sea surface height signals. First, in terms of physical mechanisms, the dominant processes of brightness reversal in optical remote sensing images are clarified, indicating that the phenomenon is jointly modulated by solar illumination geometry, surface wind conditions, and the spatial relationship with sunglint regions. Second, in terms of observation and inversion capability, minute-level high temporal resolution data make it possible to retrieve propagation speeds with high accuracy, and to continuously characterize key dynamic processes, including generation, propagation, fission, and dissipation of ISWs. Third, in terms of radar altimetry technology, the development from conventional pulse-limited altimeters to synthetic aperture altimeters and further to wide-swath interferometric imaging altimeters has realized the transition from one-dimensional along-track observation to quasi-three-dimensional wide-swath imaging, which significantly improves the capability to resolve sea surface height variations induced by ISWs and provides important constraints for amplitude inversion. Fourth, in terms of applications, trajectory prediction methods for ISWs have been preliminarily developed based on high-frequency remote sensing observations, providing a potential approach for real-time monitoring and early warning. Overall, the rapid development of multi-source remote sensing technologies is promoting the research of ISWs from qualitative observation to quantitative analysis. With the continuous integration of high-resolution observations and artificial intelligence techniques, ISW studies are expected to further develop toward high-precision inversion and operational forecasting, and to play an increasingly important role in ocean dynamics and air-sea interaction research.