We present the analytical description of gravitational two-body problem in the spinning particle limit. Recently developed equations of motion and world-line perturbation theory for particles carrying spin are reviewed. Exact circular orbit solutions, eccentric-planar orbits and the innermost stable circular orbit are found in the Kerr spacetime. Non-planar eccentric orbits including the precessional frequency of the plane are predicted in Schwarzschild spacetime. The calculations are performed with complete spin of the particle and in a fully relativistic way.