The vertical distribution, abundance, population structure and life cycle of the ice-associated copepod, Paralabidocera antarctica was studied in the fast ice near Syowa Station (69°00'S, 39°35'E) in the eastern part of Lützow-Holm Bay in 1970, 1975 and 1982. The results indicated that P. antarctica inhabited the ice-seawater interface throughout the year with a one year life cycle and was actually present in the sea ice for most of the year except the summer. P. antarctica overwintered as naupliar stages (NIV-NV) with slow development in sea ice during winter. P. antarctica population then developed rapidly and attained adulthood in the water just beneath the sea ice during spring-summer. P. antarctica depended entirely on ice algae for food throughout its whole life-span, suggesting that the ice-seawater interface provides favourable food conditions for P. antarctica. The slow development in naupliar stages in sea ice and short copepodite life span in the water suggest that P. antarctica may adapt its growth strategy to suit the varying fast ice/water interface environment.