Valuing human being is the foundation of nursing and the essence of care. Specified aspects of the health care are not compatible with the humanistic agenda. Thus, the challenge is to integrate a humanistic approach into nursing. Nursing scientists have tried to solve this problem by developing human centered theories. Internal evaluation of these theories helps decide about their applicability in solving this problem and enhancing a humanistic approach.The aim of this article is to investigate the applicability of some humanistic theories to nurses' practice. The method is critical review of related literature. Data have been gathered by consulting books, searching some data bases, and using some guiding questions. Findings revealed that humanistic nursing theories, transpersonal care, and human development are becoming specifically expanded under the influence of humanism philosophy. In these theories, human being is free and prepared to grow in a mutual interaction with the environment. Nursing flows from its presence along side others and respect for people's potentials, and has a share in human growth. Emphasis on human interactions has increased the scope of applicability for these theories, but some characteristics of these theories, users, and different context necessitate modifying these theories and developing new ones.