Abstract: Combining fuzzy soft sets and both-brank fuzzy sets theory, the definition of double both-brank fuzzy soft sets are given. The both-brank fuzzy soft subset is further defined, and both-brank fuzzy soft sets are equal. The operations of intersection, union and complement of both-brank fuzzy soft sets are specified. Several properties of these operations have been studied.The both-brank fuzzy soft set is a brand new concept, and there are many places worth studying.

Key words: Soft sets, Fuzzy soft sets, Both-brank fuzzy sets, Both-brank fuzzy soft sets

摘要： 将模糊软集和双枝模糊集理论相结合，给出了双枝模糊软集定义，进一步给出了双枝模糊软子集，双枝模糊软集相等的定义，规定了双枝模糊软集的交集、并集与补集的运算方法，研究了这些运算的若干性质。双枝模糊软集是一个全新的概念，有很多值得研究的地方。

关键词: 软集, 模糊软集, 双枝模糊集, 双枝模糊软集