  We propose an N=4 supersymmetric quantum mechanics of a charged particle on a
sphere in the background of Dirac magnetic monopole and study the system using
the CP(1) model approach. We explicitly calculate the symmetry algebra taking
the operator ordering ambiguity into consideration. We find that it is given by
the superalgebra SU(1|2)x SU(2). We show that the Hamiltonian can be written in
terms of the Casimir invariant of SU(2). Using this relation and the lower
bound for angular momentm we obtain the energy spectrum. We then examine the
ground energy sector to find that the N=4 supersymmetry is spontaneously broken
to N=2 for certain values of the monopole charge.
