Most primary brain tumor patients rely on family caregivers for support. Caregiving can be rewarding, but also leads to significant burden from unmet needs. We aimed to: (1) identify and characterize caregivers' unmet needs; (2) determine associations between unmet needs and wish for support; (3) evaluate acceptability of the Caregiver Needs Screen (CNS) and perceived feasibility in clinical practice. Family caregivers of primary brain tumor patients were recruited from outpatient clinics and asked to complete an adapted version of the CNS consisting of 33 common issues caregivers report (item scale 0-10), and the wish for support (yes/no). Participants ranked acceptability and feasibility (item scale 0-7; higher scores being positive) of the adapted CNS. Descriptive and non-parametric correlational analyses were applied. Caregivers (N = 71) reported 1-33 unmet caregiving needs (M = 17.20, sd = 7.98) but did not always wish for support (range 0-28, M = 5.82, sd = 6.96). A weak correlation was found between total number of unmet needs and wish for support (r = 0.296, P = .014). Most distressing items were patients' changes in memory/concentration (M = 5.75, sd = 3.29), patients' fatigue (M = 5.58, sd = 3.43), and signs of disease progression (M = 5.23, sd = 3.15).Caregivers most often wished support with recognizing disease progression (N = 24), and least often with managing spiritual issues (N = 0). Caregivers evaluated acceptability and feasibility of the CNS tool positively (mean scores ranged 4.2-6.2). Family caregivers experience distress resulting from many neuro-oncology specific needs, but this is not directly related to wish for support. Family caregiver needs screening could be useful to tailor support to suit their preferences in clinical practice.