This paper describes the clinical case of a patient diagnosed with diffuse large B-cell lymphoma with splenic involvement, focusing on the role of abdominal ultrasound (US) in this context. The patient experienced dyspepsia and progressive asthenia over several months so an abdominal US was performed. The US showed multiple heterogeneous and hypoechogenic focal splenic lesions together with a moderate left pleural effusion. Lymphoma was suspected due to these findings and the diagnosis was then confirmed with the performance of a CT scan and a biopsy that revealed the presence of a diffuse large B-cell lymphoma with metastatic disease. Chemotherapy containing rituximab, cyclophosphamide, doxorubicin, vincristine and prednisone was administered and the patient is currently on clinical remission. This study highlights the role of abdominal ultrasound as a useful technique in the non-invasive assessment of this entity, considering an appropriate clinical context and mainly after detecting multiple hypoechogenic splenic lesions in the US.