Research Article Received 12 June 2014 Published online in Wiley Online Library (wileyonlinelibrary.com) DOI: 10.1002/mma.3369 MOS subject classification: 35B40; 35B41; 37B55 Asymptotic behavior of solutions to a class of nonlocal non-autonomous diffusion equations F. D. M. Bezerra a * , M. J. D. Nascimento b and S. H. da Silva c Communicated by A. Miranville In this paper, we consider the nonlocal non-autonomous evolution problems u t Da.t/u C g .ˇ.Ku// in , u D 0 in R N n, where is a bounded smooth domain in R N , N 1, ˇ is a positive constant, the coefficient a is a continuous bounded function on R, and K is an integral operator with symmetric kernel .Ku/.x/ :D R R N J.x, y/u.y/dy, being J a non-negative function continuously differentiable on R N R N and R R N J., y/dy D 1. We prove the existence of global pullback attractor, and we exhibit a functional to evolution process generated by this problem that decreases along of solutions. Assuming the parameter ˇ is small enough, we show that the origin is locally pullback asymptotically stable. Copyright © 2014 John Wiley & Sons, Ltd. Keywords: pullback attractors; nonlocal diffusion equations; non-autonomous equations; evolution process 1. Introduction The purpose of this paper is to prove existence of pullback attractor and existence of a functional, which decreases along solutions for the nonlocal non-autonomous evolution equation in : u t Da.t/u C g.ˇ.Ku//, (1.1) where u D 0 in R N n, is a bounded open subset (not necessary smooth) of R N , and ˇ> 0. We will assume that a is a continuous function in R and that there exists constants a 0 and a 1 such that 0 < a 0 a.t/ a 1 , for all t 2 R, and K is an integral operator with symmetric kernel on L 2 .R N /, which is given by .Ku/.t, x/ :D Z R N J.x, y/u.t, y/dy, for all t 2 R, (1.2) where J is a non-negative function continuously differentiable on R N R N with bounded derivative, R R N J.x, y/ dy D 1 for all x 2 R N , and sup x2R N Z R N @ x J.x, y/dy S and sup y2R N Z R N @ x J.x, y/dx S, for some constant 0 < S < 1. a Departamento de Matemática, Universidade Federal da Paraíba, 58051-900, João Pessoa - PB, Brazil b Departamento de Matemática, Universidade Federal de São Carlos, 13565-905 São Carlos - SP, Brazil c Unidade Acadêmica de Matemática, Universidade Federal de Campina Grande, 58051-900 Campina Grande - PB, Brazil * Correspondence to: Flank David Morais Bezerra, Departamento de Matemática, Universidade Federal da Paraíba, 58051-900, João Pessoa - PB, Brazil. E-mail: flank@mat.ufpb.br Copyright © 2014 John Wiley & Sons, Ltd. Math. Meth. Appl. Sci. 2014