The triangular fuzzy numbers are used to represent to the object recognition problem, a new fusion method for multi-sensor data is proposed from the decision making theory. The method defines the distance matrix between all object types and unknown object. After solving the optimization problem of maximizing the standard deviations for all attributes, the weights of the attributes are obtained objectively. Hence, the result of recognition for the unknown object is given by the overall distance. This method can avoid the subjectivity of selecting attributes weights and be performed on computer easily. The simulated example verifies the feasibility and practicability of the proposed method.