At present, phacoemulsification and trabeculectomy are the most widespread surgery methods in cataract and glaucoma treatment, generally recognized as the gold standard. Among elderly patients, comorbid glaucoma and cataract are extremely prevalent, so the order of the two surgeries and the time interval between them are pivotal choices when planning treatment strategy. The reason for it is that almost any eye surgery is considered a risk factor for long-term trabeculectomy effectiveness. In attempts to solve this problem, numerous studies have been conducted on the impact of cataract surgery on filtration bleb scarring. The problem of determining the time interval between surgeries, as well as other treatment nuances, remains relevant despite the long history of research and publications. Some results are cited as general recommendations on treatment tactics (increasing the time interval between operations, using antimetabolite and anti-inflammatory therapy, minimizing intraoperative traumatism). However, currently there are no specific recommendations for one of the most important factors — the time interval between cataract extraction and trabeculectomy.