Oral cavity is often the source of local and/or general complications in patients treated by allogeneic hematopoietic stem cell transplantation (alloHSCT). According to the literature dental treatment of an adult patient prior to transplantation is based on empiric protocols elaborated by oncological clinics for their individual needs. Suggested rules often differs between each other. I this article we present different attitude to the important problem of either removing or leaving the potential dentogenic foci of infection. The analysis of the literature suggest that the most appropriate procedure is to eliminate all potential and existing sources of infection before transplantation, as long as it is possible by the amount of time remaining before beginning the conditioning chemo/radiotherapy and by the general condition of a patient. In another case dental treatment should be postponed until the posttransplantation period.