OBJECTIVE To describe and explore sleep problems in a population-based cohort of young children with cerebral palsy (CP) in Stockholm, Sweden. METHODS All children with CP, aged 5-10 years, and living in the Northern Karolinska University Hospital's catchment area were invited to participate in a cross-sectional study. Medical records obtained in the previous two-year period were reviewed, and a pre-planned parental telephone interview that included five structured questions and the Insomnia Severity Index (ISI) was conducted. RESULTS In total, 118 children, with a mean age of 7.4 years (SD 1.5), were included. Bilateral CP was present in 45%, unilateral in 37%, dyskinetic in 15%, and ataxic CP in 3%. Parents of 81% of the children participated in the interview. They reported sleep problems in 41% of their children, and in 80% of these children, night-time sleep was negatively affected by pain. Differences between the ISI total score in relation to CP subtypes (p < 0.025) and levels in GMFCS-E&R (p < 0.001) were detected, with increasing sleep problems for children with dyskinetic CP and children in GMFCS-E&R V. Sleep problems affected by pain were associated to the total score at ISI (rs = 0.83, p < 0.001, n = 95). CONCLUSIONS The results identified that sleep problems were present in more than 40% of children with CP. Sleep problems were more frequently and extensively present in children with dyskinetic CP and children in GMFCS-E&R level V. Sleep problems were associated with the presence of pain and, in particular, in the most severely affected children.