The hypodermal and hematopoietic necrosis baculovirus HHNBV has been confirmed to be the causative agent for the explosive epidermic disease of farmed shrimp Penaeus chinensis since 1993. The virus was isolated and multiplied successfully in the primary cell cultures from the lymphoid organ of the shrimp. A cell monolayer was formed in three days in the medium MPS and could be maintained for 1-3 months as the medium replaced every 4-5 days. The cytopathic effect occurred in 5 days after inoculation of the tissue extract from the diseased shrimp. The transmission electron microscopy showed many rod-shaped virions of HHNBV in the nuclei of infected cells.