PURPOSE To study the safety and efficacy of Müller muscle-conjunctiva resection (MMCR) for blepharoptosis in patients with functional glaucoma-filtering blebs. METHODS Retrospective chart review of patients who underwent MMCR in the presence of a functioning filtering bleb. Patients offered MMCR all responded satisfactorily to preoperative topical phenylephrine hydrochloride testing. Using a similar technique, MMCR was performed by 6 surgeons at 6 different centers. Two patients had simultaneous upper blepharoplasty. Postoperative slit lamp examination was performed to assess for bleb injury or infection. In addition, all patients had routine glaucoma follow-up visits to assess for bleb functioning. RESULTS Nine patients with functional filtering blebs tolerated MMCR well and had no bleb complications. All blebs remained functional after surgery. One patient had anterior chamber reaction for 10 days and another patient had foreign body sensation for 6 weeks. At 9.2-months mean follow-up time, the mean change in margin reflex distance-1 was 2.9 mm. CONCLUSION MMCR may be safe and effective in the setting of a glaucoma-filtering bleb.