This paper proposes a motion generating system that determines the parameters to the reference motion to generate motions for each emotion. In the proposed system, first the reference motion data are mapped to another space and feature vectors are obtained. After that, the feature vectors are transformed and emotional motions are generated. The parameters of the transform coefficient are determined based on the preliminary experiment. The contributions of the paper are the following two points; a proposal of the system that generates emotional motions automatically using reference motion: some finding concerning the relation between emotion and robot motion: for example, difference of degree to express each emotion, relation between the movement degree and the expressed emotion, features of motions for each emotion. We confirmed the effectiveness of the two points by experiments.