Transposition of frontalis muscle to the tarsus is an effective technique for correction of blepharoptosis with poor levator function. This is refined by division of the frontalis muscle flap into three strips, which are sutured separately to the upper tarsal border. Thirty-six patients with blepharoptosis (54 eyelids) had tripartite frontalis muscle flap procedures. The ptosis was congenital in 33 patients. Forty-eight eyelids had poor levator function. Six had fair levator function. The frontalis action ranged from 8 to 14 mm. The average of follow-up evaluation was 32 months. The postoperative results were evaluated by Berke's criteria, various sensation tests of the forehead, and presence of forehead wrinkles. The tripartite frontalis muscle flap provided an even distribution of upward pull on the tarsus without tenting the lid margin. Ptosis on superior and primary gaze, an intrinsic complication of maximal levator resection or frontalis suspension, was not observed after this procedure. Lagophthalmos was transitory, usually disappearing within 3 months. Lid lag was mild-to-moderate. Mild hypesthesia of the forehead returned completely to normal in all patients, followed more than 24 months. Slight lowering of the medial portion of the eyebrow and incomplete wrinkling of the forehead on upward gaze were mild cosmetic defects after correction in 4 patients with unilateral ptosis. The tripartite frontalis flap technique is recommended for patients with bilateral congenital ptosis and fair-to-poor levator function, and for unilateral ptosis, if either contralateral brow lift or bilateral frontalis transposition is appropriate.