Abstract: In the present paper, the morphological development of larval mantis shrimp Oratosquilla oratoria was described under experimental condition in Liaoning province, China. The Zoea 1 pseudozoea was found to develop into young squilla in 33 days at a water temperature of 23 - 26 ℃ and a salinity of 36. The morphological characteristics of each developmental stage were particularly recorded and described and apparent differences were observed in the number of plumose seta on the second antenna at Z1 and Z4 pseudozoea stages,as well as the number of side,middle and sub- middle protuberances on the telson, and the carapace length between the mantis shrimp in Liaoning province and mantis shrimp in Japan reported by Hamano.