Abstract
Until now, the equation of state of the neutron star is still an open question. Since the equation of state is usually derived from the starting point of particle physics and statistical mechanics when studying the compact star under the scheme of General Relativity (GR), GR doesn’t impinge on the physical equation of state directly. In this work, we consider the R-squared (Starobinsky) model of gravity f(R) = R + αR^2 and obtain the modified TOV equation in an attempt to give more constraints on the equation of state rather than the standard GR scheme.