Background: Early specialty palliative care for patients with advanced cancer is an evidence-based practice that improves health outcomes, yet patients do not receive timely referrals. ePRO symptom monitoring provides a ready care delivery platform to monitor patients for unmet palliative care needs and direct palliative care referral based on patient report. This study sought to obtain feasibility data for ePRO symptom monitoring of palliative care needs. Methods: We conducted a single-arm pilot study of longitudinal ePRO symptom monitoring of multidimensional palliative care needs among outpatients with advanced breast, gastrointestinal, and gynecologic cancers at an academic oncology practice. Adult patients on active treatment with a prognosis > 6 months were approached consecutively. Patients completed baseline measures and enrolled on a third-party symptom monitoring platform for 12 weeks. Patients received weekly monitoring of 14 common symptoms using the National Cancer Institute's PRO version of the common terminology criteria for adverse events (PRO-CTCAEs). Patients received monthly monitoring of palliative needs using 11 PRO items from validated measures and a clinician-developed item for patient request for palliative care. Weekly symptom alerts and monthly palliative care PRO assessments were reported to the primary oncology team for interdisciplinary clinical management. Acceptability and appropriateness of the intervention were assessed using the Acceptability of Intervention Measure (AIM) and Intervention Appropriateness Measure (IAM). Results: From May 2022 to April 2023, 29 of 37 eligible patients (78%) consented to the study, of which 25 completed baseline measures and enrolled on the platform (68% enrollment rate; most common reason for refusal was not enough time). Median age was 53 years (range 29-77), 18 (72%) female, 12 (48%) non-Hispanic White, 32% reported an ECOG-PRO score 2-3. 96% of patients met pre-defined ePRO adherence thresholds and 92% completed study end measures (1 patient censored for death). Completion of the palliative PRO items was > 94% for 9 of 11 items. Two PRO items for spiritual distress screening were skipped most often. 80% of patients reported a severe score for at least one palliative PRO symptom during the study period. Mean AIM and IAM scores were 3.92 and 4.26, respectively (range 3.25 – 5; best possible total score 5). Conclusions: Expanding evidence-based ePRO symptom monitoring to include monthly palliative care needs assessment is highly feasible, acceptable, and appropriate to patients. Adherence to PRO items was high, and most patients had at least one area of need. Future work will refine the ePRO palliative assessment with attention to spiritual distress screening and determine severity thresholds to develop a PRO-directed referral system to specialty palliative care.