In 17 out of 29 hospitalized patients (58.6%) with internal arteriovenous fistula (AVF) thrombosis a systemic streptokinase infusion was used as an alternative to urgent surgical declotting. In the remaining 12 patients (41.4%) fibrinolytic treatment was contraindicated due to the necessity for immediate dialysis, uncontrolled hypertension, active peptic ulcer, known multilevel stenoses of the fistula, or operation 8 days prior to the thrombosis. The systemic streptokinase therapy alone was successful in 9 of 17 patients treated (52.9%), 5 of 17 patients (29.4%) needed the combined therapy (streptokinase plus surgery) and in 3 of 17 patients (17.6%) the fibrinolytic therapy was unsuccessful. No serious complications attributable to the streptokinase infusion were observed. Systemic streptokinase treatment for acute AVF declotting followed by the radiological evaluation of the vessels can be a reasonable alternative to ‘blind’ surgical emergency reconstruction. The method makes it possible to identify those underlying anatomic abnormalities of the draining vein which may be localized at some distance from the anastomosis and so overlooked during surgery.