Radiation outcomes for Black patients with medically inoperable endometrial cancer (MIEC) is limited, despite this demographic comprising a higher proportion of the MIEC patient population. We report clinical outcomes and toxicities using triple tandem brachytherapy (TTB) with or without external beam radiation therapy (EBRT) for MIEC in predominantly Black patients. An IRB approved retrospective review was performed of all MIEC patients treated definitively with TTB ± EBRT from 2014-2021 at a single institution. Patients were divided based on stage. Group 1 = FIGO stage 1A/1B and Group 2 = FIGO stage 2-4B. Patients with cervical involvement were treated with TTB + ovoids. The Kaplan-Meier estimates were generated to estimate overall survival (OS) and local failure-free survival (LFFS). Local control (LC) was evaluated clinically. Acute and late toxicities were evaluated. Planning parameters for target volume(s) and OARs (organs at risk) were per ABS guidelines. Statistics reported are median values and ranges. Of 30 patients, 93.3% received TTB + EBRT. Mean age at diagnosis was 65.3 years (40.5-88.7 years). 70% of patients were Black. Median prescribed doses were 45 Gy (range: 21-50.4 Gy) for EBRT and 22.25 Gy (range: 16.5-49.1 Gy) for brachytherapy. Median BMI was 48.1 (27.8- 69) and Charlson Comorbidity Index was 4 (1-11). Patient stages were FIGO 1A/B (n = 19), 2 (n = 1), 3 (n = 1), 3b (n = 1), 3C1 (n = 3), 3C2 (n = 2), and 4B (n = 2) due to inguinal lymphadenopathy. 90% had endometrioid histology while 6.7% and 3.3% had clear cell and serous carcinoma, respectively. Median follow up was 32.1 months (1.7-93.6). Median OS for Group 1 was 50.9 months and 43.5 months for Group 2, while 1-/4-year OS was 84.2%/54.4% and 90.9%/17.5% for Group 1 and 2, respectively (p = 0.616). 53.3% of patients died of non-EC causes. The 1-/4-year LFFS was 100%/93.3% for Group 1 and 90%/70.5% for Group 2 (p = 0.113). Four patients (13.3%) developed recurrence (stage 1A/B, 2, 3C1, and 4B), but only 1 died of disease (Stage 2 with clear cell histology). After EBRT but pre-TTB, 50% (n = 15) and 16.6% (n = 5) had acute grade 2 gastrointestinal (GI) and genitourinary (GU) toxicities, respectively. After TTB treatment, 2 more patients developed acute grade 2 GU toxicity. Late toxicities were Grade 2: GU (n = 1) and GI (n = 1) and Grade 4 GI bleed (n = 1) treated with argon plasma coagulation. TTB ± EBRT for MIEC in predominantly Black patients was associated with excellent LFFS and acceptable toxicity rates, especially in early-stage MIEC with endometrioid histology. Furthermore, even in patients at high risk of death from other causes, LC may help preserve quality of life. Additional studies are needed to evaluate and optimize outcomes for Black patients with MIEC.