[en] Prospects and problems of proton therapy by means of accelerators are considered. Approaches to the solution of the problems concerning operation modes of the accelerator are formulated. It is shown that despite vivid advantage of charged particles for their applied use in beam therapy of malignant tumour it is necessary to solve two problems: extraction of special beams meeting strict medical requirements and development of technology of irradiation of malignant tumours of different localizations and construction of special equipment for execution of this technology. Engineering-technological shortcomings of proton therapy and medical-biological problems requiring reglamentation are enumerated