Molodtsov's soft set theory provides a general mathematical framework for dealing with uncertainty. The aim of this paper is to lay a foundation for providing a new soft algebraic tool in considering many problems that contain uncertainties. In order to provide these new soft algebraic structures, we introduce the concepts of ðM; NÞ-soft union hemirings and ðM; NÞ-soft union h-ideals, which are generalizations of soft union hemirings and soft union h-ideals. Using a new ordered relation and a soft intersection product (sum), we obtain some related properties. In particular, a new quotient hemiring by a ðM; NÞ-SUhemiring is constructed. Finally, we investigate some characterizations of h-hemiregular and h-duo hemirings by ðM; NÞ-SU-h-ideals.