  We investigate the heavy quark spin symmetry, i.e. the mass degeneracy of
pseudo-scalar and vector quarkonia at heavy quark limit, by using the
gauge/gravity correspondence. We allow generic D3-like geometry with a flavor
D7-brane, to avoid supersymmetric mass degeneracy. For geometries admitting
physical QCD-like properties, we find that the mass degeneracy is generically
achieved in a good accuracy, up to a few percent mass splitting. We also
compute spectra of excited quarkonia states, and discuss comparisons with
experiments and quark-model calculations.
