This paper deals with the theory of needs as a possible justification of human rights. First, it defines the concept of need, which differs from the concept of want. It states that need is, by definition, objective in nature. The paper then analyses some concepts of need (especially those of David Miller and Massimo Renzo) and examines their advantages and disadvantages in relation to justification theories (for example James Griffin's approach which is based on the idea of normative agency). According to the author, these concepts have natural-law foundations and cannot deal, in particular, with the problem of transition from facts to norms. In addition, the requirements that we usually derive from needs retain too much uncertainty. In spite of these shortcomings, using them as arguments in law and even more in politics retains a great convincing power. Its sources are difficult to identify, however, it is an important concept we use in everyday life (though in a shifted meaning). Finally, the author concludes that although needs are not able to establish human rights in a satisfactory way – provided we renounce the universal nature of these rights – they can play a very useful and important role in justifying them in certain local contexts.