Annual primary production of ice algae and phytoplankton under fast ice near Syowa Station (69°00′S, 39°35′E), Antarctica, was estimated. Mean daily production in each month from February 1983 to January 1984 was calculated with a mathematical model based on measured parameters of solar radiation, day length, attenuation coefficients of snow, ice and water, chlorophyll α standing stock, quantum yield for photosynthesis etc. Solar radiation measured at Syowa Station ranged from 0Em^h^ in June to 13.3Em^h^ in December. Relative light intensity estimated at the bottom of sea ice during the year ranged from 0 to 6.5% of incident solar radiation, due to attenuation with snow and ice. Maximum daily production of ice algae (34mgCm^(day)^) and phytoplankton (450mgCm^(day)^) was reached in December and in February, respectively. The estimated annual production of ice algae and phytoplankton was 3.5 and 17gCm^, respectively. These results indicate that summer phytoplankton production contributed remarkably to the primary production in the coastal ice-covered area near Syowa Station.