A therapeutic agent for cancer according to the present invention contains, as active ingredients, IL-18 and at least one antibody selected from the group consisting of an anti-PD-L1 antibody, an anti-PD-1 antibody, an anti-PD-L2 antibody, an anti-CTLA-4 antibody, an anti-CD25 antibody, an anti-CD33 antibody and an anti-CD52 antibody.Linvention concerne un agent thérapeutique contre le cancer contenant, en tant que principes actifs, IL-18 et au moins un anticorps choisi dans le groupe constitué dun anticorps anti-PD-L1, dun anticorps anti-PD-1, dun anticorps anti-PD-L2, dun anticorps anti-CTLA-4, dun anticorps anti-CD25, dun anticorps anti-CD33 et dun anticorps anti-CD52.本発明に係る癌治療薬は、IL-18と、抗PD-L1抗体、抗PD-1抗体、抗PD-L2抗体、抗CTLA-4抗体、抗CD25抗体、抗CD33抗体および抗CD52抗体からなる群より選ばれる1以上の抗体と、を有効成分として含有する。