We describe our experience with intrableb autologous blood injection to manage over-filtering and leaking blebs. Autologous blood was injected into 12 thin cystic filtration blebs of 12 eyes. Indications for blood injection included symptomatic hypotony in five eyes, hypotony associated with bleb leakage in five eyes, and bleb leakage without hypotony in two eyes. Seven eyes (58.3%) were classified as successes and five eyes (41.7%) were classified as failures. The mean (+/- SD) follow-up was 6.8 +/- 2.6 months. Among the eyes classified as successes, a significant increase was noted in intraocular pressure and visual acuity by a mean (+/- SD) of 5.1 +/- 2.9 mm Hg and 5.3 +/- 2.1 lines, respectively. Bleb leakage resolved in four of seven eyes. The most common complication was hyphema formation. Injection of autologous blood into a filtration bleb is an alternative procedure for management of excessive filtration or bleb leakage in selected patients.