Abstract: Micro-Doppler signature is one of the physical characteristics of the target. The radar signature of a target with micro-motion can make fine characterizations of the shape, structure, and moving state of target, which reflects the nonstationary property of a radar signal. Hence, it has great superiority in the analysis of sea clutter and target detection in the case of high sea states based on the micro-Doppler theory. In this paper, to show the need for micro-Doppler, the modeling of scattering clutter from time-varying sea surface and analysis methods of sea clutter Doppler are first reviewed based on the principles and characteristics of micro-Doppler. Then, applications and technological approaches of micro-Doppler in sea surface target detection are introduced from the perspective of micro-motion target modeling and detection methods of micro-motion signatures. Finally, future research interests are highlighted based on problems experienced in present studies.