Abstract: Pathological analysis was done on juvenile hybrid abalone(Haliotis discus discus Haliotis discus hannai) artificially infected by a spherical virus isolated from the diseased ones in Fuzhou.Examination of artificially infected juvenile hybrid abalone by optical and electron microscopy showed that the virion mainly developed in nucleus of basophilic cells in digestive gland,and led to nuclear heteromorphosis,chromatin condensation,endoplasmic reticulum expansion,and mitochondria cristae breakage in digestive gland cell and basophilic cell.Meanwhile,broken digestive gland lobule basal lamina muscle fibers,autolysis and pyknosis of microvillus and cilium columnar cell in digestive gland intestinal tract were observed.In foot muscle cells,muscle fibers were broken and vesicles emerged,together with chromatin condensation and margination.These results suggested that the digestive gland basophilic cells maybe the special target cell of this virus,the infection could cause lesion in digestive gland and digestive organs such as stomach,intestines.Atrophy due to long-term malnutrition and systemic infection would finally led to death.