The Turkish tax service in relation to family management is sometimes organized in favor of the taxpayer with the understanding of social state and sometimes in accordance with the tax security regulation in favour of the state. In these regulations, family is sometimes composed of only spouse and children, sometimes in addition to these, first degree relatives, and sometimes siblings, relationships through marriage, asendants and descendants, sometimes second degree relatives, as well as adopted child, adoptive parents, ex-partners and fiancee. The aim of this study is to determine the differences in defining family relations in various tax laws and objectives of their difference, to evaluate these differences in terms of equality and justice and to make proposals. the subject is examined for the first time in the literature. since neither the article nor the judicial decision were made in this regard, the articles referring to the concept of family were considered to be based on the basic principles of law, in terms of basic legal concepts, social state and tax security. As a result, legal gap have been identified and new regulations have been proposed in the provisions protecting the family in terms of the social state as well as in the provisions regarding the tax security measure. In the new regulation, it is proposed to add the concepts of adoptive and adoptive and brother and fiance, for social state regulations. For tax security regulations, it is proposed to adopt the concepts of ex-wife, engaged, adopted, adoptive and family, as well as heir, heir and heir.