Background: Several disease-modifying therapies (DMT) are being used in paediatric patients with multiple sclerosis (MS) despite the limited number of randomised controlled clinical trials leading to approved indication in children. Objectives: The aim of this study was to describe clinical characteristics of the Danish population of paediatric onset MS, and the patterns of DMT utilisation in patients who started treatment before the age of 18 years. Methods: We conducted a nationwide population-based cohort study, including 347 children with paediatric-onset MS (<18 years). Subjects were followed until their 25^th birthday or end of follow-up. Results: Median age at onset and diagnosis was 15.8 years and 17.2, respectively. The majority of the children had monosymptomatic presentation. In total, 140 children received DMT before the age of 18. Most started treatment with a moderate-efficacy drug (90%) of which interferon-beta was the most used (80%). However, since oral treatments became available, these have increasingly been used. During follow-up, 108 children switched or discontinued DMT. Fingolimod was prescribed more frequently than natalizumab as escalation therapy. Conclusion: We present that use of DMT in POMS varies over the observed period concurrently with the availability of disease modifying drugs with progressive use of oral and high-efficacy therapies.