中文摘要：

　 将粗糙集的理论方法用于模糊半群的研究。给出上（下）粗模糊子半群及上（下）粗模糊左（右）理想、粗糙模糊素理想等概念,研究它们的有关性质。证明上粗模糊子半群与上粗模糊理想是通常的模糊子半群与模糊理想概念的扩张。

英文摘要：

Based on rough set theory, we study the mathematical structure on the fuzzy semigroup. First, the lower and upper rough fuzzy semigroup, the left and the right rough fuzzy ideal and the rough fuzzy prime ideal are defined. Then the properties of these mathematical structures are researched. We prove that the upper rough fuzzy semigroup and the left （right,two-side） ideal are the generalization of corresponding notions defined on the fuzzv semigroup.