The spaceborne synthetic aperture radar (SAR) plays an important role in ocean observation owing to its capability of working all-day and being insusceptible to sunlight,cloudiness or rainfall.It has unique advantages in retrieval of ocean surface dynamic parameters and study of multi-scale ocean dynamic processes with high spatial resolution,multi-polarization,and multi-imaging modes.Since the late 1970s,spaceborne SAR technology has developed rapidly.When combined with big data and machine learning techniques,spaceborne SAR exhibits more powerful vitality in ocean observation.In this paper,the 5‘V’ characteristics of spaceborne SAR big data are elaborated.Then two typical cases,i.e.retrieval of the sea surface wind speed,and scientific recognition of mesoscale dynamic processes of ocean internal waves,are presented to demonstrate the integration of spaceborne SAR,machine learning,and big data in assistance of high-resolution inversion of ocean environmental factors and deep understanding of marine dynamic processes.Finally,the prospective of spaceborne SAR big data for ocean remote sensing is given.