The aim was to verify the reach of the King's theory (1981) to families of persons with systemic arterial hypertension. The study was developed analyzing the reach of this theory; verification of its applicability in the family context as related by Moreira (1999); and construction of a concept of family with chronic sick persons which is compatible with the theory. The data showed that the theory is interaccionist, with vulnerable borders, and with content elements and context not well defined. In the focalized situation, a family definition with chronic sick persons was built, showing that is possible to use it as part of part of the subject of King's theory.