Structural topology optimizations are studied widely by various methods [1-4].In this paper, a topology optimization method of space structures with stress constraints under multiple load cases based on truss-like continuum material model was presented.The space truss-like continuum material model was established.It is assumed that there was infinite number of members along three isotropic orientations at any point.The elastic matrix along material principal axis was assumed as D(t,0)=E·diag[t1 t2 t3 (t2+t3)/4 (t3+t1)/4 (t1+t2)/4],where ti is the densities of members, E elastic model.The stiffness matrix was derived as, K=∑j∑e∈Sj3∑b=1tbj∑gr(nbj)Herj,where Herj is constant matrix, gr (nbj) the function of direction nbj of member at nodej.