Primary colorectal lymphoma is a very rare disease. Primary colorectal lymphoma of diffuse large B-cells is a more frequent subtype representing 1% of all colon diseases. In a retrospective study, the clinical characteristics and treatment course of primary colorectal lymphoma of diffuse large B-cells between 1997 and 2003 were reviewed. According to Dawson's criteria, fourteen cases were identified. The average age was 65 and the ratio of men to women was 1:3. The most frequent signs and symptoms were abdominal pain (78%), diarrhea (49%) and abdominal tumor (35%). The most frequently involved regions were the cecum (42%), ascending colon (21%) and rectum (21%). Six were in Stage I, four in Stage II and four in Stage III. The 5-year survival per stage was 26, 11 and 5 months, respectively. Primary colorectal lymphoma of diffuse large B-cells usually affects the right part of the colon in an aggressive manner.