To investigate the diagnosis and treatment of primary colonic malignant lymphoma. Retrospective analysis of 14 cases of primary colonic malignant lymphoma in our hospital from 1983 to 1995. Result: All patients were treated surgically. The resection rate was 93% and the radical operative rate was 69%. Their pathological types were all NHL including 9 cases of B cell lymphoma and 6 cases of T cell lymphoma. 5-year survival rate was 35.7%. Conclusion: grasping of clinical manifestations of this disease is important to diagnosis. The combined therapies with the surgical resection as the first selection are advocated. Immunohistochemistry classification is a sensitive index to prognosis.