Introduction: Indigenous Australians with cancer tend to be diagnosed with more aggressive and advanced-stage disease, receive less treatment, have poorer survival and lower quality of life than other Australians. Reducing these inequalities requires an understanding of the supportive care needs of this cancer group. This study aims to describe the type and extent of unmet supportive care needs of Indigenous Australian cancer patients. Method: A multicentre, cross-sectional study recruited 145 Indigenous adults diagnosed with cancer in the previous 5 years in four Australian states and territories. Using a culturally specific tool, unmet needs were assessed in four domains: 'physical and psychological', 'hospital care', 'information and communication' and 'practical and cultural'. Moderate to high unmet need is that which requires some or a lot more help to be addressed. Results: Two-thirds (65%) of patients reported at least one moderate to high unmet need and 20% of patients had moderate to high unmet needs with five or more items. Overall, patients most commonly reported moderate to high unmet needs in the physical/psychological (46%) and practical/cultural domains (34%), than the information/communication (23%) and hospital care domains (16%). More specifically, 'money worries' was the most frequently reported moderate to high unmet need (20%). Conclusion: Most Indigenous Australians living with cancer experience unmet supportive care needs. Physical/psychological and practical/cultural concerns were identified as priority areas for Indigenous cancer patients. These findings may inform priority areas for intervention towards optimal care pathways for Indigenous Australians diagnosed and living with cancer.