IMPORTANCE: Low breast cancer survival in sub-Saharan Africa's young population increases the likelihood that breast cancer deaths result in maternal orphans, ie, children (<18 years) losing their mother. OBJECTIVE: To estimate the number of maternal orphans and their ages for every 100 breast cancer deaths in sub-Saharan African settings during 2014-2019 and to describe family concerns about the orphaned children. DESIGN, SETTING, AND PARTICIPANTS: Deaths occurring between September 1, 2014, and July 1, 2019, in the African Breast Cancer-Disparities in Outcomes (ABC-DO) were examined in a cohort of women diagnosed with breast cancer during 2014-2017 at major cancer treatment hospitals in Namibia, Nigeria, Uganda, and Zambia. The cohort was actively followed up for vital status via a trimonthly mobile phone call to each woman or her next of kin (typically a partner, husband, or child). MAIN OUTCOMES AND MEASURES: The number (Poisson counts) and ages of new orphans at the time of maternal death. RESULTS: This cohort study found that a total of 795 deaths resulted in 964 new maternal orphans, with deaths occurring in women younger than 50 years accounting for 85% of the orphans. For every 100 deaths in women younger than 50 years, there were 210 new orphans (95% CI, 196-225) overall, with country-specific estimates of 189 in Nigerian, 180 in Namibian, 222 in Ugandan, and 247 in Zambian Black women. For every 100 deaths of the women at any age, there were 121 maternal orphans, 17% of whom were younger than 5 years, 32% aged 5 to 9 years, and 51% aged 10 to 17 years at the time of maternal death. In follow-up interviews, families' concerns for children's education and childcare were reported to be exacerbated by the financial expenses associated with cancer treatment. CONCLUSIONS AND RELEVANCE: This study provides evidence that the number of maternal orphans due to breast cancer exceeds the number of breast cancer deaths among women in sub-Saharan Africa. The intergenerational consequences associated with cancer deaths in sub-Saharan Africa appear to be large and support the need for continued action to improve survival.