Assume that (W, g 1,∞) is a nonautonomous discrete dynamical system given by sequences (g m) ∞ m=1 of continuous maps on the space (W, d). In this paper, it is proven that if g 1,∞ is topologically weakly mixing and satisfies that g n 1 • g m 1 = g n+m 1 for any n, m ∈ {0, 1,. . .}, then it is distributional chaos in a sequence. This result extends the existing one.