aspg-21-511-1791468547 20261008140907 American Scientific Publishing Group admin@americaspg.com American Scientific Publishing Group International Journal of Neutrosophic Science IJNS 2692-6148 2690-6805 2020 8 1 Fatimah M. Mohammed Department of Mathematics, College of Education for Pure Sciences, Tikrit University, Tikrit, IRAQ Sarah W. Raheem Department of Mathematics, College of Education for Pure Sciences, Tikrit University, Tikrit, IRAQ In this paper, we present and study some of the basic properties of the new class of sets called weakly b-closed sets and weakly b- open sets in fuzzy neutrosophic bi-topological spaces. We referred to some results related to the new definitions, which we taked the case of equal in the definition of b-sets instead of subset. Then, we discussed the relations between the new defined sets by hand and others fuzzy neutrosophic sets which were studied before us on the other hand on fuzzy neutrosophic bi-topological spaces. Then, we have studied some of characteristics and some relations are compared with necessary examples. 2020 34 43 511 https://creativecommons.org/licenses/by/4.0/ 10.54216/IJNS.080103 https://www.americaspg.com/journal/21/article/511 https://www.americaspg.com/storage/5743.pdf