Proliferative glomerulonephritis with monoclonal IgG deposits (PGNMID) is a recently described entity that is only rarely associated with a hematological or lymphoproliferative malignancy. We describe the cases of two men with preexisting chronic lymphocytic leukemia (CLL) who developed endocapillary proliferative glomerulonephritis with nonorganized monoclonal IgG(1) deposits. One biopsy also showed CLL infiltration of the cortex. Both patients were treated with rituximab in addition to cyclophosphamide in one case and fludarabine in the other with significant improvement of their renal disease and CLL. This report provides additional evidence to support the use of rituximab in the therapy of CLL-associated PGNMID.