The ocean and land color instrument (OLCI) and synthetic aperture radar altimeter (SRAL) installed aboard theSentinel-3 satellite have been in orbit for operational uses. In this study, data collected from Sentinel-3 are used to investigate intal waves in the South China Sea. An intal wave is detected using an OLCI image with a resolution of 300 m, and an analysis was performed with a quasi-synchronous moderate-resolution imaging spectroradiometer (MODIS) image. The opposite characteristics of OLCI and MODIS images of the same intal wave are explained by the critical angle in brightness reversals. The unique observational geometry of the OLCI image and its influence on observations of intal waves are discussed. The distribution of σ0 and sea surfaceheight anomalies (SSHAs) induced by intal waves are studied using SRAL records. The σ0 records of SRALoccasionally show less sensitivity to the modulation of intal waves, which may be attributed to the observational geometry, while SSHAs show obvious variations. The synchronous pairing of OLCI images and SRAL records are analyzed to extract the three-dimensional sea surface signatures induced by intal waves. The analysis demonstrates that the profile of SSHAs in the surface shows an opposite phase to the profiles of intal waves in the ocean. The opposite phase relationship, observed in the remote sensing view, is also confirmed with a laboratory experiment.