Intracranial lesions in children often have good prognoses, allowing long-term survival. Cognitive functions, crucial for life quality, need more attention. Previous research has focused on adults, with pediatric studies limited by varied lesions and complex treatments. This study aims to evaluate cognitive and brain network changes in children with frontal lobe lesions, which significantly impact cognitive function, using a before-and-after comparison. The study enrolled 20 children with frontal lesions who underwent fMRI and cognitive tests before and after surgery, with only surgical treatment initially. Brain network changes were evaluated using functional metrics, and cognitive shifts were measured through test scores. Correlations were analyzed to explore brain mechanisms behind cognitive changes. Additionally, 20 healthy children underwent the same assessments for baseline data. Preliminary evidence of cognitive recovery, notably in social cognition, was observed about three months post-surgery, potentially linked to increased functional connectivity between the right lingual gyrus and right middle temporal gyrus. Children with frontal lobe lesions have demonstrated short-term postoperative cognitive improvement and associated reorganization and repair of brain networks, though this capacity for repair may diminish over time. This underscores the importance of timely rehabilitation interventions. This study offers unique insights into cognitive neuroscience and potential rehabilitation targets.