The purpose of study was to investigate the feasibility for establishing erythroleukemia model in CB6F1 mice by transplant with haploidentical mouse leukemic cell line FBL-3 and to explore the biological characteristics of FBL-3 cells in CB6F1 mice, CB6F1 and C57BL/6 mice were inoculated intravenously at doses of 1×10(3)-1×10(7) FBL-3 cells respectively. The survival time, the count of peripheral white blood cells, the percentage of erythroblasts and chromosome of these mice were observed. The liver, spleen, lung and kidney were obtained from the dying CB6F1 mice for pathological examination. The ultrastructure of erythroblasts in bone marrow and spleen was observed by transmission electron microscopy as soon as these mice died. Expression of MHC molecules and karyotype of spleen and bone marrow cell were measured. The results showed that 100% and 92.5% incidences of erythroleukemia were observed when 1×10(3)-1×10(7) FBL-3 cells had been administrated intravenously to CB6F1 and C57BL/6 mouse, respectively. There was a linear relationship between the survival time and the number of inoculated leukemic cells. The survival time of CB6F1 was longer than C57BL/6 mice inoculated the same number cell. The main targets for FBL-3 cell infiltration were liver, spleen, marrow, lung and kidney. The reaction of FBL-3 cells to glycogen staining was positive, while the to reaction peroxidase, alkaline phosphatase and butyric acid staining were negative, reaction to chloroacetic acid staining partially was positive. Virus-like particles were found in the spleen and bone marrow cells under electron microscope. Chromosomes of spleen and bone marrow cells in the majority were non-diploid, and the expression of H-2b increased, H-2d expression decreased. It is concluded that the erythroleukemia mouse model can be established in CB6F1 mice transplanted with leukemic FBL-3 cells, that provides a convenience experimental erythroleukemia model for study.