In this paper, we prove that if I is a partitioning ideal of an (m,n)-semiring R with respect to two subsets Q1 and Q2 of R, then the quotient (m,n)-semirings R/I(Q1) and R/I(Q2) are isomorphic. Also, the concepts of maximal homomorphism, steady homomorphism, one-one homomorphism and N-homomorphism are generalized for (m,n)-semirings and obtained relation between them. Finally, the fundamental theorem of semiring homomorphism is generalized for (m,n)-semirings.