It is well known that the MIC–Kepler problem, an extension of the three-dimensional Kepler problems, admits the same dynamical and symmetry groups as the Kepler problem. This paper aims to study dynamical and symmetry groups of the SU(2) Kepler problem, where the SU(2) Kepler problem is defined to be the dynamical system reduced from the eight-dimensional conformal Kepler problem through an SU(2) symmetry and turns out to be an extension of the five-dimensional Kepler problem. It is shown that the SU(2) Kepler problem admits a dynamical group SO *(8) and that the phase space of the SU(2) Kepler problem is symplectomorphic with a co-adjoint orbit of SO *(8), on which the Kirillov–Kostant–Souriau form is defined. It is further shown that the subgroups, SU(4), SU *(4), and Sp(2)× S R 5, of SO *(8) provide the symmetry groups, SU(4)/ Z 2≅ SO(6), SU *(4)/ Z 2≅ SO 0(1,5), and ( Sp(2)× S R 5)/ Z 2≅ SO(5)× S R 5, of the SU(2) Kepler problem with negative, positive, and zero energies, respectively, where × S denotes a semi-direct product. Furthermore, constants of motion for the SU(2) Kepler problem are found together with their Poisson brackets. The symmetry Lie algebra formed by constants of motion is shown to be isomorphic with so(6)≅ su(4), so(1,5)≅ su *(4), or so(5)⊕ S R 5≅ sp(2)⊕ S R 5, depending on whether the energy is negative, positive, or zero, where ⊕ S denotes a semi-direct sum. These Lie algebras are subalgebras of so *(8)≅ so(2,6).