Abstract. Let (Sn) n≥0 be a Z-random walk and (ξx) x∈Z be a sequence of independent and identically distributed R-valued random variables, independent of the random walk. Let h be a measurable, symmetric function defined on R 2 with values in R. We study the weak convergence of the sequence Un, n ∈ N, with values in D[0, 1] the set of right continuous real-valued functions with left limits, defined by [nt] i,j=0Statistical applications are presented, in particular we prove a strong law of large numbers for U -statistics indexed by a one-dimensional random walk using a result of [1].Mathematics Subject Classification. 60F05, 60J15.