In a feature modeling, problems such as ambiguities, interpretation errors, incompleteness, etc caused by informal specification occur in the modeling phase. Therefore, feature specification method and processes are suggested in this paper to resolve these problems. The structure and language of feature modeling is defined in this paper to specify various features. First, this feature model is abstracted in the meta-level to get predicates and attributes. Formal feature model specification method is proposed using multi-paradigm language. Second, Feature specification process is proposed to describe how to specify feature formally. And third, Feature interaction management is defined to solve the problems caused between specified features. Finally, the proposed feature specification method is applied to Distributed Meeting Scheduler System domain.