||In this paper, by using 0-1 linear programming a method is proposed to find efficient decision making units (DMUs). In proposed method, we put aside the production possibility set principles of the data envelopment analysis (DEA) models and only consider the observations set. The presented method compares each DMU with observed DMUs and identifies the efficient DMUs. This method consists of a one-stage algorithm. In each iteration of this algorithm, by solving a 0-1 linear programming problem, at least one efficient DMU is identified.