Purpose: The purpose of this paper is to introduce several notions, such as soft topological soft groups, soft topological soft normal subgroups, and soft topological soft factor groups, and to study their properties.Methods: We have adopted the analytical method.Results: We have studied properties of soft topological soft groups, soft subgroups, soft normal subgroups, soft factor groups, and soft homomorphisms.Conclusions: The fundamental homomorphism theorem is extended in a soft topological soft group setting.