International Journal of Neutrosophic Science IJNS 2690-6805 2692-6148 10.54216/IJNS https://www.americaspg.com/journals/show/511 2020 2020 Department of Mathematics, College of Education for Pure Sciences, Tikrit University, Tikrit, IRAQ Fatimah M. .. Department of Mathematics, College of Education for Pure Sciences, Tikrit University, Tikrit, IRAQ Sarah W. Raheem    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 2020 34 43 10.54216/IJNS.080103 https://www.americaspg.com/articleinfo/21/show/511