Based on the summer cruise conductivity-temperature-depth (CTD) data in 2001, 2002, 2006, and 2009, this paper reveals the interannual variation of spatial structure and intensity of upwelling in eastern Guangdong and southern Fujian coastal seas. Using the QuikSCAT wind data, the current and bottom temperature data from seabed-based observations, and the sea surface temperature data at the ocean station of Nan’ao, we discuss the influence of sea surface wind and tropical cyclones on the upwelling, temporal and spatial characteristics and short-term variation of the upwelling, the evolution of the upwelling, and the source of the upwelling. We show that the range and intensity of the upwelling present an interannual variation in the coastal seas between eastern Guangdong and southern Fujian. The upwelled water only reached the surface in July-August 2009. In the border area of Guangdong and Fujian, the upwelling region was narrow, and was located mostly northeastward in July-August 2006; in contrast, it was wider in July-August 2009, and was located mostly southwestward in July-August 2001. In the eastern Guangdong coastal sea, the upwelled water reached 20 m in July-August 2006, deeper than in other years. The upwelling in the study area was stronger in July-August 2002 than on the other years. A strong vertical mixing within the upwelling area induced by a tropical cyclone warmed the middle- and bottom-layer waters rapidly, and finally led to the disruption of the upwelling. The coastal upwelling appeared earlier and was stronger in eastern Guangdong coast than in southern Fujian coast. During early and mid July, the upwelling started to appear but was not permanent. It was strengthened in mid July and early August, and became weaker from mid August to early September. Finally, it disappeared rapidly during early and mid September. The upwelled water in the coastal seas of eastern Guangdong and southern Fujian came from the lower-layer cold water in the open sea of the eastern Guangdong.%利用2001、2002、2006和2009年夏季6个航次的温盐深(conductivity-temperature-depth, CTD)调查资料,揭示粤东至闽南沿岸海域上升流空间结构和强度的年际差异；并利用卫星遥感风场资料、海床基的海流和底层水温资料、广东南澳海洋站表层水温资料探讨海面风场、热带气旋对上升流的影响,上升流强度的时空特征,上升流的短期变化、生消过程及上升流的水体来源。结果表明,粤东至闽南沿岸海域上升流的范围和强度存在年际差异。上升流涌升至表层只出现在2009年7~8月航次。闽粤交界区沿岸海域,2006年7~8月航次,上升流范围较窄,且偏东北；2009年7~8月航次,范围较宽；2001年7~8月航次,范围偏西南。粤东沿岸海域,2006年7~8月航次上升流涌升高度较低,其他航次较高。研究海域2002年7~8月航次上升流强度较强,其他航次较弱。热带气旋使得上升流区海水垂向混合强烈,中下层冷水与表层暖水混合后迅速升温,上升流被破坏。粤东沿岸海域上升流强度强于闽南沿岸,出现时间也早于闽南沿岸。7月初至7月中旬,上升流开始形成,但不稳定；7月中旬至8月上旬,上升流处于强盛阶段；8月中旬至9月上旬,上升流减弱；9月上旬至9月中旬,上升流迅速消亡。粤东至闽南沿岸海域上升流的水体来源于粤东沿岸外海深层冷水。
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