In this book for the first time we introduce the notion of Smarandache neutrosophic algebraic structures. Smarandache algebraic structures had been introduced in a series of 10 books. The study of Smarandache algebraic structures has caused a shift of paradigm in the study of algebraic structures. Recently, neutrosophic algebraic structures have been introduced by the author with Florentin Smarandache [2006]. Smarandache algebraic structures simultaneously analyses two distinct algebraic structures. For instance, study of Ssemigroups analyses semigroups and groups. Thus a need for the introduction of classical theorems for groups to Sneutrosophic loops, groupoids, groups, and semigroups has become an essentiality. S-neutrosophic groups, S-neutrosophic bigroups, S-neutrosophic N-groups, S-neutrosophic semigroups, S-neutrosophic loops and S-neutrosophic mixed N-structures are introduced in this book.