The noncommutative projective scheme Projnc S of a (±1)-skew polynomial algebra S in n variables is considered to be a (±1)-skew projective space of dimension n−1. In this paper, using combinatorial methods, we give a classification theorem for (±1)-skew projective spaces. Specifically, among other equivalences, we prove that (±1)-skew projective spaces Projnc S and Projnc S ′ are isomorphic if and only if certain graphs associated to S and S ′ are switching (or mutation) equivalent. We also discuss invariants of (±1)-skew projective spaces from a combinatorial point of view.