Chronic lymphocytic leukemia (CLL) is the most common lymphoproliferative disorder worldwide. Although thoracic complications are frequent in CLL, only limited data exist regarding the etiologies of these complications. A retrospective chart review was performed on all patients admitted to a tertiary care, CLL referral center, with CLL and a respiratory complaint from 2001 through 2013, to categorize pulmonary complaints and diagnoses. There were 277 patients with CLL admitted on 409 occasions with respiratory complaints. The median age was 73 years, with a male to female ratio of 2:1. The majority of patients had a high-risk Rai classification and had received prior treatment. Common presenting symptoms included dyspnea, cough, and sputum production. The most common diagnoses were pneumonia (62.8%), with an identified organism in 44.7%, pleural effusions (31.8%), lung cancer (6.9%), and leukemic infiltrates (5.9%). Invasive procedures were performed 138 times: 70 bronchoscopies, 24 surgical lung biopsies, 10 computed tomography-guided lung biopsies, and 34 thoracenteses. In-hospital mortality was 24.9%. In a multivariable analysis, an elevated blood urea nitrogen level and creatinine, thrombocytopenia, and a presenting symptom of dyspnea correlated significantly with in-hospital mortality. Thoracic manifestations in CLL are common among hospitalized patients. Although infectious pneumonia remains most common, unusual or opportunistic infections may be increasing, and direct lung damage owing to CLL itself or to newer biologic agents are being diagnosed with lung tissue sampling. Recognition of these complications will allow earlier diagnosis, which may change management including removal of offending biologic agents or augmentation of treatment for CLL when infiltrative leukemic cells are present.