This paper deals with the existence and the asymptotic behavior of positive continuous solutions of the nonlinear elliptic system [formula] in the half space [formula] where α, β ≥ 1and r, s .≥ 0. The functions p and q are required to satisfy some appropriate conditions related to the Kato class [formula]. Our approach is based on potential theory tools and the use of Schauder's fixed point theorem.