  In general relativity, the equation of motion of the spin is given by the
equation of parallel transport, which is a result of the space-time geometry.
Any result of the space-time geometry can not be directly applied to gauge
theory of gravity. In gauge theory of gravity, based on the viewpoint of the
coupling between the spin and gravitational field, an equation of motion of the
spin is deduced. In the post Newtonian approximation, it is proved that this
equation gives out the same result as that of the equation of parallel
transport. So, in the post Newtonian approximation, gauge theory of gravity
gives out the same prediction on the precession of orbiting gyroscope as that
of general relativity.
