The frequency of infective mediastinitis after open heart surgery, according data of various authors, ranges from 0.1% to 1%. In order to decrease amount of this type of complications the specialised department with 12 beds was established at the Heart Surgery Clinic of Vilnius University in January 1, 1991. Since that time till January 1, 2002, 330 patients were operated because infective mediastinitis after open heart operations. Original method of treatment of infective mediastinitis was elaborated. Mean stay of the patients treated by means of this method ranged from 14 to 34 days (mean - 24 day). Twenty four (7.4%) patients died because of progressing sepsis (8 patients - 33.3%), heart failure (10 patients - 41.6%), multiorgan failure - 4 (16.6%), other causes - 2 (8.3%). Although there is no common method of treatment of infective mediastinitis after open heart operations, we consider our method of treatment to be effective.