Purpose: The purpose of the work is to assess acute radiation sickness of moderate severity from short-term external extremely uneven gamma-neutron irradiation and local radiation injuries of the lower extremities and right hand of III and IV severity. Material and methods: Patient T., born in 1940, at the age of 25, began working from 1965 to 1968 as an apparatchik in plant No. 1 of department 20 at Production Association «Mayak» in contact with plutonium. On December 10, 1968, at 11:30 p.m., the accident occurred. The victim was at a distance of about 50 cm from the source, which was below and mostly to the right of him. The patient was exposed to short-term exposure to neutrons and gamma radiation. A few minutes later, numbness appeared in the right half of the trunk and extremities. Twenty-five minutes later, vomiting appeared, vomiting was repeated: 8 times before admission to the hospital, at the health center, after washing in the shower, in the hospital. Made gastric lavage, intravenous administration of pentacin, diphenhydramine, glucose, bloodletting (500 ml), twice transfused blood (250 ml each), polyglucin (500 ml), promedol, atropine. On examination, slight hyperemia of the right half of the face, injection of the sclera was noted. In the blood test, made for the first time after 2 and a half hours from the start of the events, there were 9000 leukocytes, lymphocytes – 15 %. On the morning of December 11, 1968, the patient complained of a burning sensation in the right half of his face; repeated vomiting. There were 7600 leukocytes at that time. The victim was offered to go to the 6th Clinical Hospital in Moscow (Sector No. 9 of the Institute of Biophysics), the patient agreed. Examination results: A clinical description of acute radiation sickness of moderate severity from short-term external extremely uneven gamma-neutron irradiation and local radiation injuries of the lower extremities and right arm of III and IV severity is given. The features of the clinical picture of radiation sickness were entirely determined by the nature of the acting radiation factor and the position of the radiation source in relation to the victim and the associated topography of the lesion. Irradiation was directed from bottom to top and from right to left, hence the difference in exposure doses: on the right, the dose changed from bottom to top from more than 2500 rad (foot, lower leg, right hand) to less than 250–300 rad (in the head region), while in the middle – in the area from the iliac crest to the costal arch – the dose exceeded 500 rad on the left; from bottom to top, the drop occurred from a dose close to 2000 rad (foot and lower third of the lower leg) to 460 rad (in the anterior spine of the left ilium). The neutron nature of the acting radiation factor caused damage to surface tissues and visceral organs and bone marrow, the latter to a lesser extent due to the smaller contribution of the gamma factor to this accident. Conclusion: The primary reaction and laboratory data of the first days of the disease indicated a severe lesion. However, the hematological syndrome was not severe. If it were not for the pain syndrome associated with an extremely severe local injury, the general condition of the patient would not have been so severe. Local trauma, which endangered the life of the patient, led him to a deep disability. Therefore, despite the average severity of the hematological syndrome, this form of acute radiation sickness was regarded as severe. The weakening of the hematological syndrome, apparently, was caused by the extreme severity of the local injury, which played the role of a hematopoiesis stimulator.