Recently, a special kind of fuzzy mathematical programming entitled Fuzzy Flexible Linear programming (FFLP) is attracted many interests. In particular, a wide application of these models have been absorb many attentions during last decay. Hence, in this paper, we focus on one of the most important mathematical programming problems, that is, the animal diet problem, where their constraints are formulated by flexibility assumptions to be more adapt with the real situations. Furthermore, as well as the proposed methods for solving the mentioned models can solve them in two phase, while the main aim in the second phase is improving the aspiration level of the given optimal feasible solution in the first phase. In this way, in the first phase, the original FFLP problem converts it to a Multi-Objective Linear Programing (MOLP) problem, and then in phase II a weighting technique for the reduced program is introduced. Using this concept, we have solved the problem of the animal diet.