We consider a discrete time risk model in which the net payout (insurance risk){Xk,, k=1,2, …} are assumed to take real values and belong to the heavy-tailed class L ∩ D and the discount factors (financial risk) {Yk, k=1, 2, …} concentrate on [θ, L], where 0<θ<1, L<∞, {Xk, k=1, 2, …}, and {Yk, k=1, 2, …} are assumed to be mutually independent. We investigate the asymptotic behavior of the ruin probability within a finite time horizon as the initial capital tends to infinity, and figure out that the convergence holds uniformly for all n≥1, which is different from Tang Q H and Tsitsiashvili G (Adv Appl Prob, 2004, 36: 1278--1299).