Introduction: The approach and use of the term “humanization” is very much present in healthcare. However, instruments for measuring the concept of the humanization of care are yet to be designed and developed. Objective: The main objective of this study was to evaluate and validate the Healthcare Professional Humanization Scale (HUMAS) for nursing professionals. Method: The sample was made up of 338 adults, who were nurses working at health centers and hospitals, and aged between 22 and 56. Results: The results of the analyses confirm that the Healthcare Professional Humanization Scale (HUMAS) has an adequate construct validity and reliability, and defines the humanization of care as a multidimensional construct, made up of five factors: Affection, Self-efficacy, Emotional understanding, Optimistic disposition and Sociability. Conclusions: The new HUMAS scale may be an easily administered and coded instrument for approaching the humanization of care, not only in research, but also in practice.