In this paper, we give a definition of the nth fundamental group of a bound quiver and we will prove that there is an isomorphism between this fundamental group and the nth homotopy group of the CW-complex. We will first recall the definition of the fundamental group of a bound quiver and the construction of a CW-complex associated. Then we will define the nth fundamental group of an incidence algebra and will prove that this group is isomorphic to the nth homotopy groups of the CW-complex. Finally, we will give a definition of the nth algebraic fundamental group for all bound quivers of a triangular algebra.