The utilization of conceptual models without a reflection about your definitions has been being common in our country. The present work has as aim to analyze the semantic consistency of percetion concept in King´s Opened Systems Structure in two postgraduation program dissertations of the Nursing Department of the Federal University of the Ceará. It was used as theories analysis model the proposed by Chinn and Kramer. Methodological and interpretative differences was observed in the concept perception utilization in the two evaluated works. It was concluded that the authors to the adopt the concept in their studies with hypertensive patients and with children's nourished poorly mothers used different approaches.