In this thesis we have derived the vector potential to determine the analytic expressionsrnfor the magnetic eld of dipole and quadrupole components of neutron star, we developrnthe eld line equations and the magnetic eld line geometry of both dipole and quadrupolernterms. The magnetic eld varies with time and as well as the induced electric eld. Asrna result the neutron star can generate electromagnetic radiation. This electromagneticrnradiation has pressure. We have derived the radiation pressure at any distance r out sidernof the surface of the neutron star