The aim of this paper is to investigate numerically, through a finite element method, the influence of a Nano-Circular Inclusion on the interfacial stresses around a Nano-Fiber composite subjected to axial load to explain some of the causes that affect the failures of Nano-Composites. Previous investigations studied the effect of Nano-Fiber tip shape, Nano-Holes and its location around the Nano-Fiber on the interfacial stresses in a Nano-composite, while the current study focuses on studying the effect of the Nano-Circular Inclusion. It was assumed that Nano-Circular Inclusions were embedded in a discontinuous Nano-Fiber composite around a carbon Nano-Fiber composite. A tensile load was applied to the specimens in order to study the influence of these Nano-Circular Inclusions. It was found from the numerical analysis that Nano-Circular Inclusions have a great influence on the increase of the interfacial contact stresses around the Nano-Fiber in Nano-Composite.