  The Minimal superstring unification, assuming orbifold compactification,
provides interesting and rather detailed implications on physics at low energy.
The interesting feature of this model is that the masses of the spectrum are
related since all of them are functions of only two parameters: the goldstino
angle theta and the gravitino mass m_{3/2}. This fact will help us in studying
the modification of the supersymmetric magnetic moments sum rules which are
very sensitive to the supersymmetry breaking. We write these rules in case of
exact supersymmetry in a form close to the supersymmetric mass relations,
namely $ \sum_J (-1)^{(2J)} (2 J) A_J=0$, where A_J is the anomalous magnetic
moment of the spin J particle. We show that the anomalous magnetic moments of
the W-boson and the gauginos can be written as functions of theta and m_{3/2}.
Then we obtain a modified version of the supersymmetric magnetic moment sum
rule in the context of the minimal superstring unification.
