Abdominal surgery patients with postoperative septicaemia and a deep septic focus were analyzed in an attempt to identify characteristics typical of postoperative candidosis. There were 36 patients, 10 with candidosis and 26 with bacterial septicaemia. Typical for candidosis when the septic signs appeared was a history of prolonged antibiotic treatment before the operation (10/10), long courses of antibiotics (7/10), and therapy with combinations containing aminoglycoside (7/10). Operations on the small intestine were characteristic of candidosis patients (4/10). A poor clinical condition (9/10) on admission to the hospital, late onset of septicaemic symptoms postoperatively (7/10), long hospitalization (9/10), parenteral nutrition (10/10) and reoperations (9/10) were also features associated with the development of candidosis. Patients with postoperative candidosis have several characteristics on the basis of which the developing serious infection can be suspected and empirical therapy started. It may be appropriate to initiate antifungal prophylaxis in connection with operations when necrotic intestine is resected. Avoiding long courses of postoperative antibiotics could also be a measure to diminish the incidence of postoperative candidosis.