The recycling process of waste textile fiber materials could be divided into two parts: one is that waste textile fiber materials turn into recycled fibers, and the other is the use of recycled fiber process. To solve the first problem, it’s important to classify it in a reasonable way. In accordance with the main characteristics of fiber materials, new model of classification is established through three elements: color, finishing agents and twist. According to the new model of classification and different requests in recycled fiber, twenty-seven methods are proposed. Furthermore, taking waste polyester fiber materials as an example, economic cost analysis is used to assess the feasible ways in recycling waste fiber materials.