Background: Niger remains one of the countries with the highest maternal mortality burden worldwide. Approximately one in 23 women is at risk of dying from complications related to pregnancy, childbirth, or the postpartum period. Despite the implementation of the Millennium Development Goals (MDGs), the Sustainable Development Goals (SDGs), and substantial investments in maternal health over the past 15 years, progress has remained modest. The maternal mortality ratio declined from 700 deaths per 100,000 live births in 2005 to 553 in 2015 and 509 in 2017. Methods: We conducted a retrospective descriptive and analytical study at Issaka Gazoby Maternity Hospital, a tertiary referral maternity hospital in Niamey, Niger. The study covered a 12-month period from 1 January to 31 December 2025 and included all maternal deaths that met the World Health Organization (WHO) definition of maternal death. Results: During the study period, 8,002 live births and 175 maternal deaths were recorded, corresponding to a maternal mortality ratio of 2,186.9 per 100,000 live births. Maternal mortality was significantly associated with hypertensive disorders of pregnancy, grand multiparity, and lack of formal education. Direct obstetric complications accounted for most maternal deaths, with eclampsia/severe pre-eclampsia being the leading cause. Conclusion: Maternal mortality in this tertiary referral hospital remains unacceptably high and is driven by the combined effects of socioeconomic, health system, cultural, and biological factors. Strengthening antenatal care, improving timely referral systems, and ensuring rapid management of obstetric emergencies are essential to reduce preventable maternal deaths in Niger and other low-resource settings.