Introduction: There is limited evidence on the impact of COVID-19 and the related policies such as social distancing, closures of school and rehabilitation facilities on the psychosocial wellbeing of children with special educational needs (SEN). This study aims to investigate accessibility to medical and rehabilitation care for children with special needs, assess their psychosocial well-being, parental stress as well as the prevalence of childhood maltreatment in children with special needs during the COVID-19 pandemic. Method: arents of children age 2 to 12 years old studying in special schools and special child care centres throughout Hong Kong were invited through their institutions to fill in a survey consisting of questions on family demographics, child psychosocial well-being, functioning, parent-child interactions, parental stress and measures on psychological, physical maltreatment and neglect of children. Data on children with typical development was also collected at the same time during the COVID-19 pandemic by invitation t their parents through normal kindergartens and primary schools in different districts. Unpaired t-tests were used to show the differences in scores on child psychosocial well-being and parental stress between children with special educational needs and those with typical development. Simple and multiple regression analyses were conducted to explore factors associated with child psychosocial problems and parental stress during the pandemic. Results: Parents of 417 young children with special educational needs (SEN) and 25,427 agematched children with typical development completed the survey. During the COVID-19 pandemic, 66% of SEN children had disrupted rehabilitation training and 52% were affected due to changes, cancellation or inability to attend their medical appointment. Compared to children with typical development, SEN children had significant more emotional and behavioral difficulties with significantly poorer overall quality of life (68.05 vs 80.65, p<0.01) as well as physical (71.07 vs 82.63, p<0.01), emotional (73.92 vs 77.98, p<0.01), social (57.24 vs 80.14, p<0.01) and psychosocial functioning (65.57 vs 79.06, p <0.01) during the COVID-19 pandemic. Parents of SEN children have significantly higher parental stress (46.41 vs 43.36, p<0.01). 23.5% of SEN children had at least one episode of severe physical assault, 2% had very severe physical assault, 80.5% were victims of psychological aggression and 28.8% suffered from neglect. Conclusion: Our study provides empirical evidence that medical and rehabilitation care are significantly disrupted in children with special educational needs. Furthermore, SEN children are shown to have poorer psychosocial well-being and their parents have higher stress. Our study shows an alarmingly high prevalence of child maltreatment in SEN children.