Human rights are fundamental human value that all human beings have, regardless of whether they are recognized by state authorities or not. Examples of human rights are the right to life, liberty and security of person, freedom from slavery, freedom from torture, right to a fair trial, freedom of opinion, conscience and religion, freedom of expression, right to political activity, right to work, right to education, right on health, etc. Human rights belong to every man regardless of his characteristics, but there are situations when in the name of protecting some other rights or interests certain rights may be legally restricted, but then these restrictions must be in accordance with the state. Human rights are often in conflict and systematically violated around the world, but fundamental assumptions about human rights indicate that they naturally belong to people even before they are recognized and prescribed in legal or other texts. The protection of human rights in the world is dealt with by an international organization called the United Nations, which adopts a number of acts and documents for its member states. This paper will present the UN and elaborate on its bodies, institutions and functions. Also, the protection of human rights within the UN system in the Republic of Croatia will be presented.