Purpose: To investigate the safety and synergistic effect of topical bevacizumab after trabeculectomy surgery with mitomycin C (MMC). Methods: In this prospective, non-randomized, comparative interventional study, 40 eyes from 40 patients with uncontrolled open-angle glaucoma were studied after they underwent primary trabeculectomy with mitomycin C (0.02% for 2 min). Following the procedure topical bevacizumab (4 mg/mL) was used for 2 weeks 4 times daily in group A. Patients in group B received routine postoperative care. The outcome measures were the intraocular pressure (IOP), number of anti-glaucoma medications, complications, and bleb evaluation. Results: Of the 32 eyes that had at least 6 months follow-up, 16 were treated with adjuvant topical bevacizumab. The mean preoperative IOP in group A improved from 26.7 ± 9.3 mmHg with 2.8 ± 1.3 anti-glaucoma medications to 10.5 ± 2.8 mmHg with 0.7 ± 1 anti-glaucoma medications at last follow-up (P