Accurately identifying the unmet needs of community-dwelling people with dementia allows targeted support to be provided to assist these individuals to stay at home. We developed a self-report instrument to identify the unmet needs of community-dwelling people with dementia and used this to explore the prevalence and type of unmet needs present in this population. This was a cross-sectional survey of people with dementia living in the community in Australia. Participants were recruited from geriatric clinics, respite centers, aged care providers, and carers attending support groups. Eligible people with dementia were provided with a study information pack and survey which included the self-report Unmet Needs Instrument for Dementia (UNI-D), sociodemographic characteristics and survey acceptability. The UNI-D contained 26 items across 5 domains and demonstrated acceptable internal consistency, face and construct validity, and acceptability. Ninety-five eligible participants completed the survey (response rate 35%) with 85% identifying at least one unmet need (median = 4; IQR = 1-9). The items most frequently endorsed included needing more help with remembering things (64%), finding possible treatments for dementia (44%), understanding who to contact regarding a problem or concern related to dementia (36%), and to see friends and family more often (33%). The UNI-D is a promising tool to identify the self-reported needs of people with dementia. The development and rigorous testing of interventions targeting unmet needs related to health and wellbeing, dementia support, and meaningful activities appears warranted.