In this article, we present a novel theory of locally semialgebraic superspaces along with Nash supermanifolds. By adapting Batchelor’s theorem to our framework, we show that all locally semialgebraic superspaces and affine Nash supermanifolds can be derived from appropriate vector bundles. Our analysis of Nash supermanifolds involves an investigation of a topology, where closed sets are defined by Nash subsets. Within this context, we establish the softness of the structure sheaf for an affine Nash manifold. Moreover, we establish that under this topology, the higher cohomology of quasi-coherent sheaves on an affine Nash manifold vanishes completely. These results open up new directions for cohomological studies on Nash manifolds.