We study the existence of a positive solution of non-local boundary value problem in a class of non-linear terms of fractional order in infinite interval:{D_0~α+u(t)+f(t,u(t),D_(0+)~(α-1)u(t))=0,t∈[0,∞)I_0~(2-α)u(t)︱t=0=0,lim t→∞D_(0+)~(α-1)u(t)=∑_(i=1)~(m-2)β_iD_(0+)~(α-1)u(ξ_i)According to G(t,s)related properties and conditions,using Schauder fixed point theorem,we find that the boundary value problem has at least one positive solution.