On 27 February 2010, Chile experienced one of the strongest earthquakes in recorded history. The study aimed to evaluate post‐traumatic stress symptoms (PTSS) and post‐traumatic growth (PTG) in children and adolescents 12 months (T1) and 24 months (T2) after the earthquake and tsunamis in Chile in 2010. Three hundred twenty‐five children and adolescents (47.4% girls; 52.6% boys) between the ages of 10 and 16 years participated in the study. The instruments included the Revised Post‐traumatic Growth Inventory for Children by Kilmer et al., the Childhood PTSD Scale by Foa et al. and the Rumination Scale for Children by Cryder et al., as well as a scale to assess the severity of the event and a sociodemographic questionnaire. The PTSS and PTG scores decreased at T2. In addition, the main predictors of PTSS and PTG were disruptive experiences, losses after the event and intrusive and deliberate rumination during the previous year. These results enhance understanding of factors related to PTG, improve the ability to predict PTSS and PTG in children and adolescents following natural disasters, and inform the design of intervention strategies to promote better mental health in those affected.