Let F=∪i=1kSdi be the union of pairwise vertex-disjoint k stars order d1+1,…,dk+1, respectively, where k≥2 and d1≥⋯≥dk≥1. In this paper, we present two sharp upper bounds for spectral radius F-free (bipartite) graphs characterize all corresponding extremal graphs. Moreover, minimum least eigenvalue adjacency matrix an graph are obtained.