Objective The impact of childhood differentiated thyroid carcinoma (DTC) on psychosocial development has not yet been studied. The aim of this study was to evaluate the achievement of psychosocial developmental milestones in long-term survivors of childhood DTC. Design and methods Survivors of childhood DTC diagnosed between 1970 and 2013 were included. Reasons for exclusion were age <18 or >35 years at follow-up, a follow-up period <5 years or diagnosis with DTC as a second malignant neoplasm. Survivors gathered peer controls of similar age and sex (n = 30). A comparison group non-affected with cancer (n = 508) and other childhood cancer survivors (CCS) were also used to compare psychosocial development. To assess the achievement of psychosocial milestones (social, autonomy and psychosexual development), the course of life questionnaire (CoLQ) was used. Results We included 39 survivors of childhood DTC (response rate 83.0%, mean age at diagnosis 15.6 years, and mean age at evaluation 26.1 years). CoLQ scores did not significantly differ between survivors of childhood DTC and the two non-affected groups. CoLQ scores of childhood DTC survivors were compared to scores of other CCS diagnosed at similar ages (n = 76). DTC survivors scored significantly higher on social development than other CCS, but scores were similar on autonomy and psychosexual developmental scales. Conclusions Survivors of childhood DTC showed similar development on social, autonomy, and psychosexual domains compared to non-affected individuals. Social development was slightly more favorable in DTC survivors than in other CCS, but was similar on autonomy and psychosexual domains.