We have investigated the relation between the two-point spatial correlation function and the density profile of the dark matter halo in the strongly non-linear regime .
It is well known that when the density fluctuation grows into dark matter halo whose density profile is \rho \propto r ^ { - \epsilon } ( \frac { 3 } { 2 } < \epsilon < 3 ) on almost all mass scales , the two-point spatial correlation function obeys a power law with the power index \gamma = 2 \epsilon - 3 in the strongly non-linear regime .
We find the form of the two-point spatial correlation function , which does not obey the power law when the power index \epsilon is smaller than \frac { 3 } { 2 } , such as the density profile \rho \propto r ^ { -1 } around the center of the halo which is proposed by Navarro , Frenk & White ( 1996,1997 ) .
By using the BBGKY equation in the strongly non-linear regime , it is also found that velocity parameter h \equiv - \langle v \rangle / \dot { a } x is not a constant even in the strongly non-linear regime ( \tilde { x } \equiv x / x _ { nl } \rightarrow 0 ) although it is a constant when \epsilon > 3 / 2 and then the two-point spatial correlation function can be regarded as the power law .
The velocity parameter h becomes 0 at the non-linear limit of \tilde { x } \rightarrow 0 , that is , the stable clustering hypothesis can not be satisfied when \epsilon < 3 / 2 .