The distribution and general population characteristics of Pseudanchialina pusilla (Sars, 1883) were evaluated based on zooplankton collections obtained from different seasonal surveys conducted in 2004-2006 in the eastern Arabian Sea as part of a multidisciplinary project Marine Research on Living Resources Assessment Program. P. pusilla exhibits a wide range of variations in its population dynamics in the study area and their population density over the entire study area ranged from 0 to 12000 ind.1000 m-3. The highest abundance was during the Southwest monsoon (SWM) of 2004 (43.4% of the total sampled population) followed by the inter monsoon (IM) of 2005 (37.0%) and Northeast monsoon (NEM) of 2006 (19.6%). Temperature and salinity appeared to have little influence on the general distribution of P. pusilla in the study area. The number of egg/embryo carried by females varied from 4 to 8 exhibited a positive correlation with female and size. The egg diameter ranged from 0.30-0.42 mm and was independent of female size. Mature individuals total body size varied from 2.6-3.2 mm and 2.5-3.3 mm in males and females, respectively