A severe radiological accident involving an industrial radiography source containing Ir occurred in China. A worker was seriously exposed, which resulted in acute radiation syndrome. Initial whole-body dose was estimated at 1.51 Gy (95% Confidence Interval: 1.40-1.61 Gy) using biological dosimetry. This work performed a physical dosimetric reconstruction to provide more detailed exposure information for clinical treatment, using sitting and standing posture phantoms constructed by adjusting the Chinese reference adult male polygon surface phantoms to the worker body. A 3D view of photon flux in the body and dose distribution of local tissue with isodose lines in his legs were displayed by THUDose, and the absorbed doses of organs were present. These results were compatible with clinical symptoms and analysis, and they were helpful in assisting in the planning of therapy and in alerting physicians of potential high-risk organs. The physical dosimetric reconstruction could provide more detailed information for clinical treatment in a radiological accident with respect to obtaining local dose estimates.