The PGRP-SC2 gene from A. sinica was cloned. PGRP-SC2 was highly expressed under change of Gram bacteria. PGRP-SC2 was found to be transcribed in different tissues and organs of A. sinica. PGRP-SC2 is crucial to A. sinica early embryo development. PGRP-SC2 was involved in response of innate immunity against bacteria in A. sinica.