Based on zooplankton samples collected in Antarctic krill Euphausia superba Dana fishing grounds adjacent to the South Shetland Islands (CCAMLAR subarea 48.1) and South Orkney Islands (CCAMLAR subarea 48.2) in the Antarctic peninsular region during the period of January 23 to February 13, 2010, the abundance density, length distribution and development stage composition of Thysanoessa macrura G. O. Sars were studied. Samples were collected by two types of plankton nets, one was vertically towed plankton net with 330μm mesh size, and the other was horizontally towed surface plankton net with 500μm mesh size. Sea surface temperature (SST) ranged from 0.37 ℃ to 2.49 ℃, with a mean of 1.58 ℃ ; surface salinity ranged from 32.91 to 34.32, with a mean of 33.88. T. macrura was found in most of the survey area; vertical sample showed that the mean density was 261.6 ind/1000m3 in subarea 48.1 and 391.5 ind/1000m3 in subarea 48.2, and the density was positively correlated to SST (P=0.04). T. macrura was composed of individuals at all development stages from CII to adults and dominated by furcilia. The range and mean total length of furcilia, juvenile and adult were 2.74～6.80 mm, 5.15 mm; 6.81～16.20 mm, 8.15 mm and 15.40～20.70 mm, 17.98 mm respectively. The growth rate at the various stages of furcilia ranged from 0.013～0.064 mm/d; no significant difference was found between the two subareas (P=0.37), and the global mean was 0.040 mm/d. The spawning season of T. macrura was estimated to be at the end of September to October in subarea 48.1 and at the beginning of October to mid November in subarea 48.2. T. macrura appeared more frequently in the surface towed net both in terms of station and in terms of specimen, indicating that the surface towed net can be an effective supplement to the vertically towed net in study of the spatial distribution and growth of krills in general.