  The properties of super-Eddington accretion disks exhibit substantial
distinctions from the sub- Eddington ones. In this paper, we investigate the
accretion process of a magnetized neutron star (NS) surrounded by a
super-Eddington disk. By constructing self-similar solutions for the disk
structure, we study in detail an interaction between the NS magnetosphere and
the inner region of the disk, revealing that this interaction takes place
within a thin boundary layer. The magnetosphere truncation radius is found to
be approximately proportional to the Alfv\'en radius, with a coefficient
ranging between 0.34-0.71, influenced by the advection and twisting of a
magnetic field, NS rotation, and radiation emitted from an NS accretion column.
Under super-Eddington accretion, the NS can readily spin up to become a rapid
rotator. The proposed model can be employed to explore the accretion and
evolution of NSs in diverse astrophysical contexts, such as ultraluminous X-ray
binaries or active galactic nucleus disks.
