  We investigate the structure of the dark matter halo formed in three
different cold dark matter scenarios. We performed N-body simulations of
formation of 13 cluster-sized halos. In all runs, density cusps proportional to
$r^{-1.5}$ developed at the center. This result was independent of the
cosmological models we simulated. We could not reproduce the cusp shallower
than $r^{-1.5}$, which was obtained in some of previous studies. We also found
that in all runs the density structure evolves in a self-similar way, even in
$\Omega\ne 1$ universes. These results show that the formation of structural
form is a process decoupled from a background cosmology.
