Hepatosplenic T-cell lymphoma is an uncommon neoplasm characterized by a lymphoid infiltrate within the sinusoids of the liver, spleen, and bone marrow, without significant nodal involvement. The majority of cases express the gammadelta T-cell receptor and are associated with an isochromosome 7q cytogenetic abnormality. Recently, a small number of cases have been reported that express the alphabeta T-cell receptor. Here, we report our findings of a case of an S100-positive hepatosplenic alphabeta T-cell lymphoma in a 20-year-old woman who presented with pancytopenia and hepatosplenomegaly. The case adds to the growing literature of hepatosplenic alphabeta T-cell lymphomas.