Abstract:Let Hm be the complex Hilbert space with dimension m, S(Hm?Hn) be all the quantum states acting on complex bipartite Hilbert space Hm?Hn and Ssep(Hm?Hn) be the convex set of comparable quantum states.φ:S(Hm?Hn)→S(Hm?Hn)be a surjective map andφ(Ssep(Hm?Hn)=Ssep(Hm?Hn)).For some r∈R+\\{1}, if φ satisfies Tsallis entropySr(tρ+(1-t)σ)=Sr(tφ(ρ)+(1-t)φ(σ))for any ρ,σ∈S(Hm?Hn) and for any t∈[0,1], there exist unitary operators Um, Vn acting on Hm, Hn such that φ(ρ)=(Um?Vn)ρ(Um?Vn) for any ρ∈Ssep(Hm?Hn).