  N-body simulations of dark matter halos show that the density is cusped near
the center of the halo. The density profile behaves as $r^{-\gamma}$ in the
inner parts, where $\gamma \simeq 1$ for the NFW model and $\gamma \simeq 1.5$
for the Moore's model, but in the outer parts, both models agree with each
other in the asymptotic behavior of the density profile. The simulations also
show the information about anisotropy parameter $\beta(r)$ of velocity
distribution. $\beta\approx 0$ in the inner part and $\beta\approx 0.5$
(radially anisotropic) in the outer part of the halo. We provide some
distribution functions $F(E,L)$ with the constant anisotropy parameter $\beta$
for the two spherical models of dark matter halos: a new generalized NFW model
and a generalized Moore model. There are two parameters $\alpha$ and $\epsilon$
for those two generalized models to determine the asymptotic behavior of the
density profile. In this paper, we concentrate on the situation of
$\beta(r)=1/2$ from the viewpoint of the simulation.
