We report two cases of malignant lymphoma of mucosa-associated lymphoid tissue arising in the conjunctiva. Case 1, an 18-year-old girl, showed her left lower conjunctival swelling for four months and Case 2, a 29-year-old man, showed similar lesions on both his eyes for one year. Histologically, both cases revealed monomorphous dense lymphoid infiltrates invading the overlying conjunctival epithelium with diffuse patterns. The infiltrates were composed of small lymphocytes admixed with centrocyte-like cells within the conjunctival epithelium and stroma in association with B-cell lineage.