Background <p>Community-acquired pneumonia (CAP) is one of the primary causes of morbidity and mortality in children. Autophagy-related protein 7 (Atg7) is a key autophagy effector enzyme that regulates immunity and cell death in combination with other Atg proteins. The involvement of Atg7 in phagocytosis indicates that Atg7 deficiency could increase vulnerability to infection.</p> Methods <p>Atg7 was measured by ELISA in the serum samples of 105 children divided into three groups: group A (35 patients with complicated pneumonia); group B (35 with noncomplicated pneumonia) and group C (35 healthy controls). Atg7 was correlated with the severity of pneumonia and the development of complications.</p> Results <p>Atg7 was significantly greater in patients with pneumonia (the mean in group A was 458.90 ± 136.89 ng/L, and the mean in group B was 677.40 ± 151.44 ng/L) than in controls (the mean in group C was 153.61 ± 45.46 ng/L) in response to infection, but its level was significantly lower in patients with complicated pneumonia than in patients with noncomplicated pneumonia (<i>p</i> &lt; 0.001).</p> Conclusion <p>Serum Atg7 increases in response to infection but children with complicated pneumonia have a defective autophagic response to infection which leads to severe complications. Further research is essential to validate these findings across diverse populations and explore potential confounding factors affecting serum Atg7 levels.</p>