The research has been devoted to the study of acute toxicity of preparation based on derivative of indolocarba- zole - LCS-1208 in mice of both sexes and in rats of both sexes at intravenous and intraperitoneal administration of the drug. In the experiments the laboratory animals - outbred white rats and hybrid mice (C57Bl/6JxDBA2)Fl (B6D2F1) have been used. On the results of study has been obtained the calculated toxic doses of novel preparation based on derivative of indolocarbazole at intraperitoneal administration of the drug in mice of both sexes.