i will talk about the scattering operators on conformally compact einstein manifolds based on the work of graham and zworski. a conformally compact einstein manifold comes with a conformal manifold as its conformal infinity. i will show scattering operators, as spectral property of the bulk space, in many ways are related to global conformal property of the infinity. i will in particular talk about a recent joint work with colin guillarmou on the relation of the location of real scattering poles and the yamabe constant of the conformal infinity.