Background: This study aimed to investigate the pulmonary side effects of chemotherapy drugs in children with Acute Lymphocytic Leukemia (ALL) three years after treatment. The results could be of great help in managing lung complications in pediatric oncology patients. Materials and Methods: This cross-sectional descriptive study included 50 patients (22 males and 28 females) with ALL. Data were collected from patients' files, including age, sex, duration of illness, last dose of chemotherapy, and medications such as PEG.Asparginas, Cyclophosphamid, thioguanine, Dexamethason, cytarabin, cytosin.arabinosid, vincristine, mercaptopurine, and methotrexate. Pulmonary function tests (Forced Vital Capacity (FVC), FEV1 (Forced Expiratory Volume in the first second)) were assessed by spirometry. Results: Out of 50 patients, 47 (94%) did not have pulmonary disorders, while 3 (6%) had pulmonary dysfunction. Forty-seven patients (94%) did not have respiratory symptoms. FVC results showed that 45 patients were normal, and 5 were abnormal. Similarly, 45 patients had normal FEV1, and 5 had abnormal results. Spirometry results were normal in 45 patients and abnormal in 5. A significant relationship was found between the use of these drugs in different doses and spirometry results, recurrence rate, and pulmonary complications (P <0.05). No significant relationship was observed between pulmonary dysfunction and other drugs (P> 0.05). No correlation was found between pulmonary complications due to chemotherapy with duration of chemotherapy, patient age, and patient gender (P> 0.05). Conclusion: Pulmonary dysfunction and respiratory syndrome were observed in 6% of patients receiving chemotherapy. A significant relationship was found between the frequency of pulmonary and respiratory complications with some chemotherapy drugs in children with ALL. Further research is needed to optimize treatment strategies and minimize lung complications in pediatric oncology patients.