The present invention is directed to the combination therapy of an afucosylated anti-CD20 antibody with a MDM2 inhibitor for the treatment of cancer, especially to the combination therapy of CD20 expressing cancers with an afucosylated humanized B-Ly1 antibody and a MDM2 inhibitor.本発明は、癌の治療のための、MDM2阻害剤とのアフコシル化抗CD20抗体の併用療法、特にアフコシル化されたヒト化B-Ly1抗体とMDM2阻害剤、例えばテムシロリムス又はエベロリムスでのCD20発現癌の併用療法に関する。