  Properties of the vortex state in helical p-wave superconductor are studied
by the quasi-classical Eilenberger theory. We confirm the instability of the
helical p-wave state at high fields and that the spin-polarized local density
of states M(E,r) appears even when Knight shift does not change. This is
because the vorticity couples to the chirality of up-spin pair or down-spin
pair of the helical state. In order to identify the helical p-wave state at low
fields, we investigate the structure of the zero-energy M (E = 0, r) in the
vortex states, and also the energy spectra of M (E, r).
