PURPOSE Therapeutic alliances (TAs) between oncologists and patients are bonds characterized by mutual caring, trust, and respect. We here relate oncologist characteristics and behaviors to TA among Latino and non-Latino patients with advanced cancer. METHODS Participants included non-Latino oncologists (n = 41) and their Latino (n = 67) and non-Latino White (n = 90) patients with advanced cancer who participated in Coping with Cancer III, a multisite, US-based prospective cohort study of Latino/non-Latino disparities in end-of-life cancer care, conducted 2015-2019. Oncologist characteristics included age, sex, race, institution type, Spanish language proficiency, familismo practice style (emphasis on family) and clinical etiquette behaviors. Patient-reported TA was assessed using the average score of six items from The Human Connection scale. Hierarchical linear modeling (HLM) estimated effects of oncologist characteristics on TA. RESULTS Of 157 patients, a majority were female (n = 92, 58.6%) and age younger than 65 years (n = 95, 60.5%). Most oncologists were male (n = 24, 58.5%), non-Latino White (n = 25, 61%), and age 40 years and older (n = 25, 61%). An adjusted HLM in the full sample showed that Latino patient ethnicity was associated with significantly lower TA (β = −.25; P < .001). In an adjusted stratified HLM for TA, among Latino patients, oncologist familismo practice style (β = .19; P = .012), preference using first names (β = .25; P = .023), and greater Spanish fluency (β = .11; P < .001) were positively associated with TA. In contrast, familismo practice style had no impact on TA for non-Latino White patients. CONCLUSION Latino patients with advanced cancer had worse TAs with their oncologists versus non-Latino patients. Modifiable oncologist behaviors may be targeted in an intervention designed to improve the patient-physician relationship between oncologists and their Latino patients with advanced cancer.