Although small lymphocytic lymphoma (SLL) is an indolent lymphoma, approximately 5% of cases can transform to a higher-grade lymphoma, rarely Hodgkin lymphoma (HL). We report the fine-needle aspiration (FNA) results of 6 cases of SLL/chronic lymphocytic leukemia (CLL) that transformed to HL. FNA findings were correlated with the histologic features and clinical follow-up. The patients included 5 men and 1 woman, ranging in age from 49 to 72 years at the time of SLL/CLL diagnosis with time for development of HL ranging from 0 to 95 months (mean, 49.3 months). The FNA diagnoses were SLL with HL transformation (2 cases), SLL with large atypical cells (1 case), and atypical lymphoid proliferation with large atypical cells (3 cases). Flow cytometry performed in 5 cases (2 FNA specimens) demonstrated a monoclonal B-cell population with CD19/CD5 coexpression. The presence of large atypical mononucleated and binucleated cells in lymph node FNA specimens from patients with SLL/CLL with progressive adenopathy should raise the possibility of transformation to HL. In these cases, histologic confirmation is always recommended, not only to differentiate HL transformation from other entities but also for subclassification of HL.