Background: Routine electronic health record (EHR)-based screening and resource referral to address social determinants of health (SDOH) have been established in adult primary care clinics and the emergency department of New England’s largest safety-net hospital. The burden of SDOH in safety-net oncology patients is less well-studied. This study aimed to understand the social needs of this vulnerable patient population and evaluate the need for implementation of SDOH screening in the oncology clinic. Methods: Patients with lung or head and neck cancer seen in consultation in the Department of Radiation Oncology at Boston Medical Center between 3/2019-1/2020 were identified. EHRs were reviewed for receipt of THRIVE, an EHR-based screening and referral model addressing SDOH. Associations between patient demographics and SDOH screening were evaluated. Results: A total of 104 head and neck (n = 53; 51%) and lung (n = 51; 49%) patients were identified. Median age was 65 years (interquartile range 57.5-72). The majority of patients were male (71.2%), and English-speaking (82%). Whites, Blacks, and Asians comprised 43%, 38%, and 3% of patients, respectively. Fifteen patients were Hispanic (14%). Patients were most likely to have private health insurance (n = 41; 39%), followed by joint Medicare-Medicaid plans including senior and community health plans for elderly (n = 27; 26%), Medicaid (n = 17; 16%), and Medicare (n = 17; 16%). 83 of 104 patients (79.8%) were screened for at least one SDOH domain, with 55 patients (66%) screened before presentation in radiation oncology clinic. Transportation to medical appointments (16%), food insecurity (14%), and inability affording medications (10%) were the most prevalent concerns among these oncology patients. Housing insecurity, utilities, caregiving, unemployment, and education were identified social concerns for 4-5% of patients. The majority of patients who had at least one social need requested resources to assist them (71%). Age, gender, race, language, and insurance status were not associated with receipt of the SDOH screener (p≥0.1). Conclusions: Safety-net oncology patients report significant social needs. Routine SDOH screening and resource referral should be considered in these vulnerable patients.