Objective: Hematological malignancies very rarely involve the breast. The aim of this study is to retrospectively evaluate B-mode ultrasound (US) and elastography (ES) findings of breast involvement by hematologic malignancies with clinical outcomes. Materials and Methods: All core-needle biopsy results that were performed at our tertiary breast center from January 2013 to September 2016 were searched. Our search revealed 9 patients with breast involvement either by leukemia or lymphoma. All patients were examined using B-mode US and ES. US and ES findings were analyzed with the consensus of two radiologists, and clinical outcomes were noted. Results: The mean age of the study population was 41.6 years (range, 20-83 years). Two patients showed diffuse hypoechoic parenchymal infiltration. The elasticity assessments of these lesions were soft and intermediate. The remaining 7 patients had mass lesions. The elasticity assessment of these masses according to Breast Imaging Reporting and Data System US was as follows: Soft (n = 1), intermediate (n = 4), high (n = 2). Conclusions: It is important to consider that hematologic malignancies may appear as soft or intermediate lesions on ES. Patients' history and clinical background should help us to consider breast involvement. In addition, the clinical outcomes may not be related with elasticity assessments.