Purpose: Bleomycin is a chemotherapeutic agent that causes lung toxicity. Bleomycin is mostly used in the treatment of germ cell tumors(GCT) and Hodgkin Lymphoma(HL) in childhood cancers. In this study, we aimed to detect bleomycin toxicity to the lung in the early period. Materials and methods: Pulmonary functions of patients aged 5 years and older who were admitted to the Division of Pediatric Oncology with germ cell tumors and Hodgkin Lymphoma between 2012 and 2022, who received bleomycin treatment and were in remission for at least 6 months were evaluated. The evaluation of respiratory function was based on history, physical examination, posteroanterior chest radiography and pulmonary function test. Results: There were 109 patients with GCT and 122 patients with HL. The number of patients with GCT who entered follow-up and lived were 59, those with HL were 89]. The number of patients who received bleomycin treatment, were in remission for at least 6 months and underwent PFTs were 46 for HL and 12 for GCT. There were 21 patients with PFT abnormalities. Of these patients, 3 were diagnosed with GCT and 18 were diagnosed with HL. The type of PFT abnormality in the majority of patients was restrictive disorder. Conclusion: The absence of respiratory symptoms in 90% of patients with PFT abnormalities shows the importance of PFT in asymptomatic patients. Patients who have received bleomycin as part of treatment should also be followed-up for late pulmonary toxicity.