Over last decade, a number of studies has concerned possible implications of "old" medical drugs, as additional tools for cancer treatment. The main reasons for extension of drug indications are as follows: (1) limited efficiency or high costs of targeted oncogene protein inhibitors or specific monoclonal antibodies for therapy; (2) new molecular targets were revealed for some drugs traditionally used to other therapeutic purposes; and (3) sufficient decline of development costs for the new therapies performed by the "old" drugs. The list of such repurposed drugs now includes dozens of medications commonly used for treatment of cardiovascular diseases, diabetes mellitus, epilepsia, different inflammatory disorders. The present review deals, mainly, repurposing of anti-infectious drugs, including those used in prevention and management of infectious complications occurring in cytostatic therapy of leukemia and lymphomas, e.g., tetracyclines, erythromycin derivatives, as well as fluoroquinolones, antiviral compounds etc. The antitumor effects were of these candidates for repurposing were demonstrated upon screening of their cytostatic effects in leukemic and other cancer cell lines. Some studies were performed in experimental tumor-bearing animals. Only few clinical trials were carried out in patients with leukemias and lymphomas following hematopoietic stem cell transplantation (HSCT), which showed some positive effects of antibacterial drugs in terms of graft-versus-host disease (GvHD) prevention, or prolonged survival of the patients. Controlled clinical trials of common anti-infectious drugs are required for this repurposing.