  We develop a novel approach to the dark matter halos in the context of 4
dimensional Einstein--scalar-Gauss-Bonnet gravity to reproduce the flat
rotation curves of galaxies. Moreover, the Gauss-Bonnet coupling describes the
interior structure of the galaxies, while there is a presence of a scalar field
$\phi $ in the galaxy edges. This can provide an interesting interpretation for
the functional coupling $f(\phi )$. We discuss how this comparison can
naturally drive the observed percentages of matter and dark matter in the
Universe. The effective mass range\ in our model is $% 10^{-2}kg-10^{3}kg$,
which is in good agreement with the constraints on primordial black holes.
