In this paper, taking the magnetic R. N metric as a space-time background, we derive a static magnetic field in this curved space-time. Substituting the derived static magnetic field as a source of gravitational field into the right-hand side of Einstein-Maxwell equation, we solve the Einstein-Maxwell equation with a step-by-step approximation method by the first degree, and derive a new metric. This metric describes the external field of a neutron star with magnetic charge and magnetic dipole moment. We still discuss various kinds of celestial bodies with a characteristic parameter that satisfies X<1, X=1 and x>1, and get some properties which some electric charged celestial bodies do not possess.