Let V = V_0 +V_1 be a vertex operator superalgebra. Then V has a canonical automorphism \sigma of order 2 from the super structure. We assume V is rational and C2-cofinite. We will discuss the super \sigma-twisted modules,connection between representations of V and V_0 . We will also explain how the representation theory of V is related to the 16-fold way conjecture in category theory. This talk is based on joint work with Chongying Dong and Richard Ng.