Currently, a large amount of data has demonstrated that many types of tumor cells, in contrastto their non-transformed forms, are characterized by the translocation of intracellular heat shock proteins70 kDa (HSP70) to the surface of the plasma membrane. This made it possible to classify HSP70 exposedon the cell surface as a tumor-associated antigen and was the basis for searching the opportunities for thepractical use of this phenomenon in clinical oncology. A significant argument in favor of the prospects of suchstudies was the discovered ability of HSP70, present on the surface of target cells, to enhance the cytotoxicactivity of NK cells. In this regard, the work of many research groups is devoted to developing approaches toincreasing the level of membrane-associated HSP70 in tumor tissues. At the same time, given the presenceof such proteins on the surface of many types of tumor cells, the use of monoclonal antibodies that interactwith HSP70 molecules for antitumor therapy can be considered as one of the promising approaches. It is wellknown that antibody preparations that selectively interact with cancer cells can be used for targeted antitumorimmunotherapy. Previously, we obtained a panel of six B cell hybridomas producing monoclonal antibodiesto the inducible and constitutive forms of human HSP70, directed to various epitopes of this molecule. Itis significant that three varieties of hybridomas produced antibodies with specificity for binding sites on theC-terminal domain of the HSP70 molecule, and the second trio of monoclonal antibodies were specific toepitopes on the N-terminal domain of HSP70, while almost all known commercial antibodies interact onlywith C-terminal fragments of HSP70. In this work, we conducted a comparative study of the binding of theobtained antibodies to these proteins localized in different types of cells, both in the intracellular space andon the cell surface.The results obtained allow us to consider the identified varieties of monoclonal antibodies that most effecti-vely recognize surface HSP70 as a promising basis for the creation of new drugs for antitumor immunotherapy.