Abstract: Abstract ：The diseased 12-week-old scatter-feed Huainanwang native chickens in a farm were anatomized. The white tumor was found in liver of the diseased chicken; The myocardium was found thickened and suspected tumor vegetation was found; The splenatrophy was observed and the color of the section was dark. The suspected case was molecularly diagnosed by PCR assay using specific primers of subgroup J avian leukosis virus. A specific DNA band with the size of 545 bp was obtained, indicating that the tissues of the diseased chicken were positive for subgroup J avian leukosis virus. In a conclusion, the suspected ease was pathologically and molecularly diagnosed as infection of subgroup J avian leukosis virus.