Abstract: The topology optimization method of structures under uncertain loads is studied based on interval theory. The topology optimization truss-like structure is expressed by a truss-like material model. The topology optimization method of a least-weight truss-like structure with stress constraints is derived based on the interval theory. The strain state at any point under the most unfavorable load case is determined by interval analysis, at which the orientations and densities of members in truss-like continuum are optimized by a fully-stressed criterion. A structure is analyzed and optimized iteratively until it converges. The discrete trusses are established based on the member distribution field in truss-like continuum. Its effectiveness is verified by several numerical examples, which show that the structural topology under uncertain loads is more reasonable than those under certain loads.