ABSTRACT Objective: Describe the construct validation process of the instrument “Nursing care for the assessment, prevention and treatment of cutaneous xerosis in the elderly”. Method: Methodological study carried out with 101 nurses in four hospitals in the great João Pessoa, between July and September 2018. Construct validation was performed through exploratory and confirmatory factor analysis, in addition to the consistency check by Cronbach’s alpha. Results: Through the factorial analysis, three factors of the instrument construct were defined: treatment performed for cutaneous xerosis, preventive care for cutaneous xerosis and skin evaluation, with a total explanation variance of 47.77%. In Bartlett’s sphericity test, p <0.001 was obtained, and the general Cronbach’s alpha was 0.811. Conclusion: The instrument proved to be valid and reliable, contributing to the training and practice of nurses as an integral part in the process of caring for the elderly.