Introduction: The care of the preterm newborn (PNB) is a challenge for nurses, as it is necessary the structuration of a comprehensive care plan which facilitates similar conditions to those of the intrauterine state. To achieve the goals of care in this population, it is imperative to use the Nursing Process, starting with the assessment phase that makes it possible to identify the real needs of preterm infants and state nursing diagnoses which will guide individualized interventions that represent an improvement in their health and quality of life, and thus recognize the advantages of this tool from the training practice. Method: Presentation of a clinical case of a PNB to whom was applied the format for valuation of health domains of the School of Nursing at the Industrial University of Santander (UIS) composed by thirteen (13) domains that establish the Taxonomy II of NANDA (NANDA International Nursing Diagnoses) and adapted for the newborn. Results: The use of the Nursing Process, in the stages of assessment and diagnosis from the academy, allowed students to identify four altered domains, nine nursing diagnoses, giving priority to one of them according to the defining characteristics evident in a case study. Conclusions: The assessment by health domains from the NANDA Taxonomy II allowed to identify nursing diagnoses of the
preterm newborn, from a global perspective, integrating the theoretical components of physical assessment in a real scenario of care.