Existence of ethical climate of professionalism as the climate governing hospitals under study from the nurses’ perspective indicates that professional principles based on ethical codes and attention to professional ideals, which are those of health improvement, are the first driving factor in development of ethical climate in hospitals. Considering scientific development of various subjects of health sciences, especially nursing in Iran and also development of complementary education, it is expected to see its effects in hospitals in the shape of impact on ethical climate and rule of professional principles.