The world of science is developing very rapidly. This can be explained by people's desire to know everything, for example, the origins of life, the structure of the human organism, the secrets of the universe, etc. One of the branches of science is regenerative medicine, which includes stem cell research. In general, stem cells are unique cells in the human body, which have the ability to renew themselves and specialize into liver cells, kidney cells or spinal cord cells from unspecialized cell types. There are numerous advantages and disadvantages to the use of stem cells in the treatment of the most common diseases in the world. The object of this research project is to evaluate the benefits and risks of using stem cells in the treatment of global diseases. It deserves to be studied, because stem cells are a constitutive part of the human organism and their capabilities must be explored, in order to be able to use them in therapies for diseases such as Alzheimer's, Parkinson's, diabetes mellitus, spinal cord injuries and heart disease. It is important to know the possible risks of using stem cells, as well as their benefits. Basically, stem cells are unspecialized cells of the human organism, which have a remarkable ability to renew themselves and specialize with new functions. They have distinctive properties to develop into different cell types, such as brain, nerve or liver cells, etc. Stem cells repair dead cells; furthermore they can divide without any limitation. In general, there are four sources of stem cells: embryonic stem cells; fetal stem cells; stem cells from adult humans; stem cells from the umbilical cord. Saxena (2009) points out that stem cells are divided into two categories based on their origin. These stem cells are undifferentiated...... focus of the article......ntions. iii. How can neural disorders, such as Parkinson's, Alzheimer's and spinal cord injuries, be treated with stem cells and what are the concerns about applying this therapy in humans? Scientists suggest that stem cells have great potential in the treatment of neurodegenerative disorders, such as Parkinson's, Alzheimer's and spinal cord injuries, but at the same time these therapies carry numerous risks, which may be explained by the lack of investigation in this field and require more time to perform. Parkinson's disease is a type of neurodegenerative disease, which is characterized by the death of special cells that produce a chemical called dopamine. Dopamine is responsible for human movement because it carries signals to the brain. The loss of these cells can cause symptoms such as tremors, stiffness and disability in movement (Wu 2010).