  In order to reveal the difference between the latest neutron star observation
experiment GW170817 and the existing theory, we mainly consider the effect of
the nucleon radius on the neutron star from the existing theory. We believe
that the effect of nucleon radius in neutron star is not negligible, and the
mass radius of nucleon should be used instead of the charge radius. The nucleon
mass radius is set as $r_m = 0.55\pm0.09$ fm from the new measurements. It is
considered as an input to the "Excluded Volume Effects" model in the equation
of state of nuclear matter. We propose a novel neutron star mass-radius
relation by using proton mass radius is consistent with the observation
GW170817.
