Introduction: The psychological impact of the COVID-19 pandemic on the general population has been widely studied. However, few studies have been carried out on children, even though they are experiencing a difficult situation and major stress that may expose them to significant psychological suffering. We are interested in how children perceive these emotional changes during the confinement associated with the COVID-19 pandemic. The aim is to understand the impact of the pandemic and containment on children. To do this, we assessed the prevalence of depression, anxiety and perceived post-traumatic stress in school-age children, looking for factors associated with these psychopathological dimensions with a view to better management and intervention to reduce the possible negative effects of this situation. Methodology: This is a cross-sectional study based on gathering information from all primary school pupils in Fez, who responded freely and voluntarily. The study was carried out over a period of two months, from June 2020 to August 2020, using an online self-questionnaire and psychometric evaluation scales: QIPS, CDI, CRIES-13. Results: 330 students met our inclusion criteria. The mean age of our participants was 8.68 ± 1.94 years, with a minimum of 6 years and a maximum of 12 years. There was a slight female predominance, with 168 girls (50.9%) and 162 boys (49.1%). Most of the pupils (95.2%) lived in urban areas, 92.7% of the children had married parents, and 64.5% of our participants had parents with a university education. Almost half of the children had a family income of more than Dhs10,000 per month. Only 2.1% of the children had a psychiatric history, 16.7% of the children had a history of somatic illness, 22.1% of the participants had a family psychiatric history, 11.2% of our participants had experienced a stressful event in their lives and 22.1% had parents who had previously experienced a stressful event. Evaluation of the CRIES-13 scale showed that 39.4% had a positive score of over 30 in favour of significant symptoms of post-traumatic stress disorder, a probable depressive state (CDI score>15) was revealed in 26.1% of the children, and with regard to anxiety disorder, the mean score in our sample was 32.27 (±8.147) with a median of 29. The analytical study showed a statically significant relationship between certain socio-demographic characteristics, namely: parents' low level of education, living with divorced parents, low monthly family income and negative psychological impact during the pandemic. On the other hand, female gender was correlated with the occurrence of anxiety. Our study also revealed other correlations, notably between the presence of a personal history of psychiatric or somatic illness and the occurrence of depression, family psychiatric history, and the experience of a stressful event by the child and parents were factors strongly associated with the three psychological disorders studied. Factors related to the child's lifestyle, such as the practice of physical activity at home, a daily study period of less than 2 hours, and dissatisfaction with distance learning, were associated with psychological distress during confinement. In addition, certain personality traits seemed to be implicated in the worsening of this condition during confinement: the presence of a relative with covid-19, the child's knowledge of the pandemic, and the fear that the pandemic would continue. Conclusion: The COVID-19 pandemic has had a severe impact on the general public, particularly children, psychological interventions identifying and targeting children at risk are urgently needed, and future studies are warranted to design and evaluate the effectiveness of interventions.