Background: Emotional support (ES) is the most frequently reported support need among older adults with cancer. Yet, the association of ES with cancer outcomes is largely unknown. This study examined the association of ES with health-related quality of life (HRQoL), mental health, and survival among older adults with GI malignancies. Methods: We included older adults (≥60y) newly diagnosed with GI cancer and undergoing a self-reported geriatric assessment (GA) at first clinic visit. Self-reported ES, measured by the Medical Outcomes Survey was the primary exposure. Outcomes included physical and mental HRQoL as measured by the Patient-Reported Outcomes Measurement Information System® (PROMIS) 10-item global assessment, anxiety and depression as measured by the PROMIS Anxiety and Depression Short Form 4a, respectively, and one-year, two-year, and overall survival. Linear regression evaluated the association between ES and t-scores of physical/mental HRQoL. Logistic regression evaluated the association of ES with anxiety and depression. Models were adjusted for age, race, sex, and cancer type/stage. Kaplan-Meier curves and log-rank tests evaluated the association between ES and survival outcomes. Results: Overall, 795 participants were included. The median age was 68 (IQR: 64-74) and patients were 58.0% male, and 74.6% White. The most common cancers included colorectal (37.9%) and pancreatic (30.8%), with mostly advanced staged disease (Stage III/IV: 72.1%). A majority (77.6%) had adequate ES. Patients with inadequate ES were more likely to be Black (31.5 vs. 20.8%, p=0.005), disabled (24.1 vs. 10.4%, p<0.001), and widowed/divorced (54.2 vs. 24.8%, p<0.001). After adjustment, patients with inadequate ES had lower physical and mental HRQoL t-scores (Physical β: -3.35, 95% CI: -5.25, -1.46; Mental β: -2.46, 95% CI: -4.11, -0.81) and higher odds of depression (aOR: 2.22, CI: 1.34-3.69). There was no statistically significant association with anxiety (aOR:1.15, CI: 0.73, 1.81). No differences were observed between patients with inadequate versus adequate ES in one-year, two-year, or overall survival (Log-Rank tests: one-year, p=0.952; two-year, p=0.606; overall, p=0.584). Conclusions: Older adults with inadequate ES have higher odds of poor physical and mental HRQoL and depression, but no difference in survival compared to those with adequate ES. Further work is necessary to determine if interventions to improve ES also improve HRQoL and depression.