Background While several studies have found executive function deficits in adults and maltreated children with posttraumatic stress disorder (PTSD), there are few data on executive function in children and adolescents with PTSD related to natural disasters. The objective of this study was to test executive function changes over time in children and adolescents with PTSD after a magnitude 8.0 earthquake in Sichuan, China. Method A sample of 34 children and adolescents with diagnosed PTSD following the Sichuan earthquake and 66 matched controls exposed to the same earthquake but without PTSD participated in the study. Executive function was assessed using a battery of interviewer‐rated neuropsychological tests and the guardian‐rated Behavior Rating Scale of Executive Function (BRIEF) at 4‐ and 12‐month after the earthquake. Results Children and adolescents with PTSD performed similar to controls in executive function at 4‐months after the earthquake. Both groups improved significantly in similar domains of cognition during the following 8 months. The PTSD group exhibited daily deficits in emotional control compared with the controls at the 4‐month assessment, but the differences disappeared during the following 8 months. Conclusions Children and adolescents with PTSD related to a natural disaster have deficits only in the emotional control domain of executive function compared with controls exposed to the same disaster, but even these deficits did not persist.