Aim – to describe a clinical case of atypical course of complications of peptic ulcer disease and the possibility of timely urgent diagnosis. Materials and methods – a clinical case of atypical course of a perforated duodenal ulcer. The clinical case described demonstrates the difficulties of diagnosis in case of lack of time, a dubious clinical picture, ambiguous X-ray data, which requires a more thorough clinical analysis of the available information by urgent brigade of surgeons. For the timely diagnosis of surgical complications of peptic ulcer disease, it is necessary to use modern imaging methods.