Abstract: Alzheimer’s disease is a neurodegenerative disorder clinically characterized by cognitive dysfunction and by deposition of amyloid plaques, neurofibrillary tangles in the brain. The study investigated the therapeutic effect of combined mesenchymal stem cells and erythropoietin on Alzheimer’s disease. Five groups of mice were used: control group, Alzheimer’s disease was induced in four groups by a single intraperitoneal injection of 0.8 mg kg-1 lipopolysaccharide and divided as follows: Alzheimer’s disease group, mesenchymal stem cells treated group by injecting mesenchymal stem cells into the tail vein (2x106 cells), erythropoietin treated group (40 μg kg-1 b.wt.) injected intraperitoneally 3 times/week for 5 weeks and mesenchymal stem cells and erythropoietin treated group. Locomotor activity and memory were tested using open field and Y-maze. Histological, histochemical, immunohistochemical studies, morphometric measurements were examined in brain sections of all groups. Choline transferase activity, brain derived neurotrophic factor expression and mitochondrial swellings were assessed in cerebral specimens. Lipopolysaccharide decreased locomotor activity, memory, choline transferase activity and brain derived neurotrophic factor. It increased mitochondrial swelling, apoptotic index and amyloid deposition. Combined mesenchymal stem cells and erythropoietin markedly improved all these parameters. This study proved the effective role of mesenchymal stem cells in relieving Alzheimer’s disease symptoms and manifestations; it highlighted the important role of erythropoietin in the treatment of Alzheimer’s disease.