Stem ceils transplantation is one of the potential therapeutic strategies for Alzheimer's disease (AD). Many animal models following stem cell transplantation showed improvement in memory and cognitive function. However, the pathological changes in AD, such as arnyloid beta deposits, negatively affect the survival and differentiaition of stem cells. Stem cells transfectcd with neprilysin or administration of phenserine could at-tenuate these adverse effects. Genetic modification of stem cell by over expression of neurotrophic factors could attenuate the adverse effects not only on stem cells but also on degenerative neurons. Further investigation on how to overcome the adverse effects of phathological factors in AD on stem cells and maximize the therapeutic effects of stem cells would support the hope for introduction of stem cells transplation into clinical application.