T-Cell Rich B-Cell Lymphoma (TCRBCL) is relatively a new entity, lately classified as a morphologic variant of Diffuse Large B-cell lymphomas (DLBCL). It consists (1-3) % of all B-cell lymphomas. The rate is far less when describing cases of primary splenic involvement with TCRBCL. Pathologically, TCRBCL is described as a limited number of scattered, large, atypical b-cells embedded in a background of abundant t-cells and frequently histiocytes. The similarity of this malignancy with other types makes it difficult to distinguish between them. Thus, it needs expertise in both clinical and pathological fields to make the right diagnosis.Here, we present a case of an adult male patient whose first presentation and previous medical history of renal colic misguided the initial diagnosis and suggested another colic episode as the underlying ailment. However, further physical, radiological and histopathological investigations uncovered the presence of primary TCRBCL within spleen with no involvement of other sites. Moreover, unusual pathologic finding of CD3 positivity was proved by immunohistochemistry.