Giant cell arteritis (GCA) causes systemic symptoms; however, involvement of the lungs is relatively rare compared to other rheumatic diseases such as rheumatoid arthritis and systemic sclerosis. Diagnosis and treatment of GCA complicated by chronic lung diseases can be challenging. In this case, an 87-year-old male presented with the chief complaints of systemic muscular pain and cough. The patient was eventually diagnosed with GCA complicated by chronic bronchitis. Although GCA treatment with chronic bronchitis is uncertain, we treated the patient with tapering doses of prednisolone and tocilizumab, which were effective. In older patients with systemic muscular pain and cough, GCA can be considered a differential diagnosis, and tocilizumab can be a reliable treatment in cases complicated by lung diseases, similar to other rheumatic diseases.