Interstitial pneumonia (IP) is a significant adverse effect of chemotherapy in B-cell non-Hodgkin's lymphoma (NHL) patients. This study aimed to identify the clinical characteristics, risk factors, and treatment outcomes associated with IP in these patients. A retrospective review of 615 NHL patients treated at the Fourth Hospital of Hebei Medical University from 2016 to 2021 identified 50 patients with IP post-chemotherapy as the case group. A propensity score matched control group of 55 patients without pneumonia was established. Clinical profiles, risk factors, and treatment outcomes were evaluated. The IP incidence was 8.13% (50/615) in B-cell NHL patients. Multivariate analysis revealed liposomes, elevated lactate dehydrogenase (LDH), and erythrocyte sedimentation rate (ESR) as independent risk factors for IP. Receiver Operating Characteristic (ROC) curve analyses suggested that alterations in LDH and ESR could predict IP risk. The conclusion suggests that IP is associated with liposomal doxorubicin-induced lung injury and other cytotoxic chemotherapy, possibly due to Rituximab (RTX)-induced immune imbalance. Given the potential of IP with pulmonary infections, high-risk patients may need prophylactic antibiotics and appropriate corticosteroid therapy.