The effects of nanosized lithium carbonate particles on muscle tissue structure and development of experimental hepatocarcinoma-29 transplanted into the hip were studied in CBA mice. Necrotic changes in all structural components of the muscle were detected after intramuscular injection of nanosized lithium carbonate particles to intact animals. Regeneration of the muscle fibers after lithium carbonate treatment was associated with a significant increase in macrophage count, number of microvessels, activation of fibroblasts, and complete recovery of the organ structure. Injection of lithium carbonate nanoparticles at the periphery of tumor growth caused tumor cell necrosis, destruction of the vascular bed, and attraction of neutrophils and macrophages to the tumor focus. After the preparation was discontinued, the tumor developed with lesser number of vessels, smaller tumor cells, and lesser deformation of the cell nuclei structure.