SUBJECT: the invention relates to magnetic material physics and to medicine, in particular to magnetotherapy (hyperthermal electromagnetic therapy) of malignant neoplasm. The inventive method consists in injecting a material particles exhibiting a high (maximum) magnetocaloric effect into a tumor, wherein said material has a magnetic ordering temperature close (approximately) to a human body temperature and is selected from a group containing precious metals, rear-earth elements (metals) and the alloys or intermetallic compounds thereof. Said method makes it possible to destroy cancer cells and is selected such that it is ecologically pure and non-toxic
