Oral cancer patients' supportive care needs during the postoperative period can impact their family caregivers' burden. The purposes of this study were to (1) examine patients' perceived levels of supportive care needs, (2) examine caregivers' perceived levels of caregiving burden, and (3) examine the predictive factors for caregivers' caregiving burden with newly diagnosed oral cancer patients during the postoperative period. A cross-sectional, correlational study was conducted. One hundred twenty-two pairs of eligible patients and caregivers were recruited from the otolaryngology and plastic/reconstructive inpatient wards in a medical center in northern Taiwan. A set of questionnaires was used to assess patients' needs, including the Karnofsky's Performance Status Index, Cancer Needs Questionnaire Short Form, Head and Neck Specific Needs Questionnaire, and Background Information Form; the caregivers' burden was evaluated using the Caregiver Reaction Assessment, Inventory of Socially Supportive Behavior, and Characteristics of Care Experiences Form. In general, patients reported having high overall supportive care needs with the highest level in the "health system and information" domain among 6 needs domains. Caregivers had moderate levels of caregiving burden, with the highest level in the "self-esteem" domain among 5 caregiving experience domains. Factors significantly related to those burdens across 5 domains of caregiving burden were caregivers' social support, patients' physical and daily living needs, patients' health system and information needs, and patients' psychological needs. Postoperative oral cancer patients experienced relatively high unmet supportive care needs, and caregivers perceived moderate levels of caregiving burden. Healthcare professionals should systematically assess patients' and caregivers' problems and provide timely supportive care clinically.