There is electromyogram(EMG) as one of biological signals generated along with motions of the human body. This EMG has information corresponding to condition of power, tenderness of motions and motion level. Therefore, it is thought that it is useful biological information for analyzing person's motions. Recently, researches on this EMG have been actively done. For instance, it is used as a control signal of electrical arms, because EMG can be gathered from the remaining muscle about upper-extremity amputee. In addition, the pointing device that uses EMG has been developed. In general, EMG is measured from a part with comparatively big muscular fibers such as arms and shoulders. There is a problem that placing and removing the electrode is inconvenient when EMG is measured by placing the electrode in the arm and the shoulder. Therefore, if we can recognize wrist motions using EMG which is measured from the wrist, the range of application will extend furthermore. Currently, we have constructed a wrist motion recognition system which recognizes the wrist motion of 7 types as an object by using the technique named Simple-FLDA as a feature extraction technique. However, motions with low recognition accuracy were observed, and it was found that the difference of the recognition accuracy is significant at each motion and subject. Because EMG is highly individual and its repeatability is low. Therefore, it is necessary to deal with these problems. In this paper, we try the construction of a system that can learn by giving incremental data to achieve an online tuning. The improvement of the algorithm of Simple-FLDA that incremental learning becomes possible was tried as a technique for the construction of online tuning system. As a recognition experimental result, we can confirm the rising of the recognition accuracy by incremental learning.