The East China Sea Subbureau of National Bureau of Oceanography carried out a comprehensive investigation in the East China Sea (28°-34°N, west to 127°E) from December, 1977 to November, 1978. From the planktonic ostracoda samples, we have discovered three male or female specimeans belonging to Euconchoecia, but different from five known species of the genera. Based on the observation and comparision, we identified them as a new species of Euconchoecia and named them as Euconchoecia bifurcata n. sp. to demonstrate their unique characteristic of having bifurcate front alorgan.