Deriving from Kuroshio, the warm currents are important sources of heat energy for the East China Sea, especially in winter. Their strengths will greatly influence the structure of temperature of the sea and affect further the variation and development of the ecosystem. By analyzing temperatures and fronts of the warm currents in the East China Sea in the winter of 2003, and comparing them with the situations in different years, it can be seen that the strengths of Kuroshio, Taiwan warm current and Tsujima warm current are nearly their highest in history, while the Yellow-sea warm current is only slightly stronger than the average. And the comparison of the temperature of the Jiangsu offshore waters in this winter with its temperatures in different years shows little difference from average, and it fluctuated with the climate severely. Therefore, the stronger warm currents only affected the surrounding areas and did not spread to offshore waters. The cross-correlation analyses indicate that Kuroshio impacts Tsushima warm current and Taiwan warm current acutely, but touches little on Yellow-sea warm current and offshore waters. And the temperature of Kuroshio varies with the temperature in the tropical Western and Central Pacific Ocean.