Abstract:This paper first reports the composition, distribution and similarities among various flats of nano-and microalgae in sand and gravel covered by ice and snow in the intertidal zones of the Zhongshan Station in Larsemann Hills (69°21′—69°25′S, 76°00′—76°25′E), East Antarctica. The samples were collected from six gravel-sand flats during January 1989 to February 1990. The following distributional characteristics of nano-and microalgae in the intertidal zones were revealed: small cell size, high cell abundance and up to 80% of cells less than 30 μm. The average cell abundance was 1011.2× 103 and 661.82 × 103 cells per gram of gravell-sand in January and February respectively. The maximum cell abundance of nano-and microalgae occurred at station B. One hundred and sixty taxa of nano-and microalgae were observed, of which, 45 species occurred at all substations, and Navicula glaciei was the dominant species.