Let I be a normal hyperideal of a Krasner (m, n)-hyperring R, we define the relation ≡ I by x ≡ I y if and only if f (x, −y, (m−2) 0) ∩ I ∅, which is an equivalence relation on R. By means of this idea, we propose rough soft hyperrings (hyperideals) with respect to a normal hyperideal in a Krasner (m, n)-hyperring. Some lower and upper rough soft hyperideals with respect to a normal hyperideal are investigated, respectively. Further, we define the t-level set U(µ, t) = {(x, y) ∈ R × R| z∈ f (x,−y, (m−2) 0) µ(z) ≥ t} of a Krasner (m, n)-hyperring R and prove that it is an equivalence relation on R if µ is a fuzzy normal hyperideal of R. By means of this novel idea, we propose rough soft hyperideals by means of fuzzy normal hyperideals in Krasner (m, n)-hyperrings. Finally, two novel kinds of decision making methods to rough soft Krasner (m, n)-hyperrings are established.