We successfully conducted the first high-resolution near-seafloor magnetic survey of the Central,Southwest,and Northern Central Basins of the South China Sea (SCS) during two cruises on board Chinese R/V HaiYangLiuHao in October-November 2012 and March-April 2013,respectively.Measurements of magnetic field were made along four long survey lines,including (1) a NW-SE across-isochron profile transecting the Southwest Basin and covering all ages of the oceanic crust (Line CD);(2) a N-S across-isochron profile transecting the Central Basin (Line AB);and (3) two sub-parallel NE-SW across-isochron profiles transecting the Northern Central Basin of the SCS (Lines D and E).A three-axis magnetometer was mounted on a deep-tow vehicle,flying within 0.6 km above the seafloor.The position of the tow vehicle was provided by an ultra-short baseline navigation system along Lines D and E,while was estimated using shipboard GPS along Lines AB and CD.