Macrophage migration inhibitory factor (MIF) might mediate its biological activities through a classical receptor-mediated or non-classical endocytic pathway. JAB1 (C-Jun activation domain-binding protein-1) promotes degradation of the tumor suppressor p53 and the cyclin-dependent kinase inhibitor p27. When MIF and JAB1 are bound to each other in intracellular sites, MIF inhibits the positive regulatory effects of JAB1 on the activity of AP-1. The intestinal parasite, Anisakis simplex, has an immunomodulatory effect. The molecular mechanism of action of As-MIF and human JAB1 proteins remain poorly understood. In this study, As-MIF and hJAB1 were successfully expressed and purified with high solubility. We modeled the 3D structure of As-MIF and its interaction with hJAB1 by homology modeling based on the structure of the Ace-MIF. We provide evidence indicating that the MIF domain of As-MIF interacts directly with the MPN domain of hJAB1 and four structure-based mutants of As-MIF and hJAB1 disrupted the As-MIF-hJAB1 interaction.