  There are constructed exact solutions of the quantum-mechanical Dirac
equation for a spin S=1/2 particle in the space of constant positive curvature,
spherical Riemann space, in presence of an external magnetic field, analogue of
the homogeneous magnetic field in the Minkowski space. A generalized formula
for energy levels, describing quantization of the motion of the particle in
magnetic field on the background of the Riemann space geometry, is obtained.
