Objective: To study the natural history of AIDS, caused by blood transfusion., Methods: All HIV infections and AIDS patients were from Hebei province, including those infected through blood transfusion around 1995, that were identified as through general census of former commercial plasma donors (FCPDs). Among those objects being observed during the incubation period, 354 had HIV infections (including 142 cases infected via plasmapheresis and 212 cases caused by transfusion) but had not been treated by HAART before the onset of disease. Objects being observed during the survival period, 141 were AIDS patients (including 57 cases infected via plasmapheresis and 84 cases causes by transfusion) but had not been treated by HAART before and after the onset of disease. All infectors and AIDS patients were under follow-up on the progress of illness or death, respectively., Results: By December 31, 2010, the cumulative incidence among HIV infections was 88.70% (314/354), with the incidence density as 9.14/100 person-years (314/3435.75) and the median incubation period was 113 months. Of 142 HIV infections in the blood donation group and 212 infections in the blood transfusion group, the incubation periods were 112 months and 115 months, respectively. All of the 141 patients died 34 months after the onset, with the death-strength as 204.70/100 person-years (141/68.88) and the period of survival was 4 months. Among those 57 FCPDs infections, they were all died 24 months after the onset, with the death-strength as 250.66/100 person-years (57/22.74) and the survival was 3 months. The other 84 infections who were blood recipients, all died 34 months after the onset, with the death-strength as 182.05/100 person-years (84/ 46.14) and the survival was 4 months., Conclusion: Through this study, we noticed that the natural history of all the AIDS patients was caused by blood transmission. It was important to evaluate the natural history of HIV epidemics among both FCPDs and blood recipients, occurred before and after 1995.