BackgroundThe impact of COVID-19 on children is a vital topic to cover since the quarantine lasted for months, and limited research explored this effect locally in Arab countries. We studied the impact of the COVID-19 lockdown on the psychosocial well-being of children aged 1-18 years who were living in Saudi Arabia during the time of the pandemic.MethodA total of 387 participants' responses were collected using online questionnaires (valid and reliable) composed of three sections with open and close-ended questions by the child's legal guardians. This cross-sectional study was conducted in Saudi Arabia and targeted children aged 1-18 years of both genders using a convenience sampling technique. One questionnaire assessed the child's behavior and sleep pattern, while the other evaluated child's activity and social skills. We analyzed the data using Statistical Package for Social Sciences (SPSS) version 20.0 (IBM Corp., Armonk, NY).ResultsHalf of the children were 1-6 years (196; 50.6%), and the caregivers of more than half (225; 58.2%) were mothers. Two-thirds (234; 60.5%) of the children were male. Apart from a poor appetite for food and eating (non-nutritional) junk food, which was not significant (p-value > 0.05), all other factors, behavior, sleep patterns, activity, and social skills, all other factors were significantly affected by COVID-19 (p<0.05).ConclusionThis study found that the COVID-19 pandemic had a negative impact on children's psychosocial well-being. It is recommended to implement actions that aim to enhance the ability of children to cope with challenges.