Abstract: To establish a commercial hatchery in crabs a mass seed production experiment was conduced in the blue swimming crab, Portunus pelagicus. It undergone 5 zoeal and I megalopa stage. The larvae took 24.3 days to complete their cycle. The rotifer (Brachionus plicatilis) and Artemia nauplii were provided as feed for the larval forms. The survival rate decreases with increasing larval stages. While, larval duration increases with increasing larval stages. Maximum survival (71.6%) was reported in I zoea and minimum (4.3%) was in Megalopa when metamorphosed into Ist crab instar. Initially the larvae took 3 days to reach the next stage (I-IV stage). It was 4-5 days for the later stages (IV-Ist crab instar). Mortality and cannibalism is a common problem encountered during the study period. The reason for the mortality and cannibalism is discussed in detail.