The northeastward current (NC) southeast of the Ryukyu Islands is estimated using an inverse technique with hydrographic section data collected in December 2000. The inversion results show the NC flowing over the continental slope with a subsurface maximum velocity of 34 cm s-1 at 270-dbar depth southeast of Okinawa and 67 cm s-1 at 400-dbar depth east of Amami-Ohshima. The NC volume transports are nearly equal at the two lines (~15 Sv), and their vertical profiles exhibit similar subsurface maximum structure at both lines. These results strongly suggest that the NC off Amami-Ohshima originates from the NC off Okinawa during our observation period.