The purpose of this study was to analyze movements of the incisor point during chewing (chewing movements) of the patients with craniomandibular disorders (CMD) and healthy subjects, to classify the parameters of chewing movements and to clarify the relationship between classified parameters and CMD.Chewing movements of right and left sides were recorded with Sirognathograph Analysing System. The number of analyzed sides was 80 in 40 healthy subjects and 171 in 95 patients with CMD (90 in 50 patients with anterior disk displacement with reduction (Click), 42 in 25 patients with anterior disk displacement without reduction (Lock), and 39 in 20 patients with myofascial pain dysfunction syndrome (MPDS)). The 68 parameters of chewing movements were divided into 10 categories by a principal component analysis.The results were as follows:1. Distinctive parameters between healthy subjects and patients with CMD were irregularity of opening and closing path near the occluding point, unstable opening and closing speed, disturbance of rhythm, unstable occluding point and limitation of lateral closing path.2. Characteristics of chewing movements were delay of maximum opening and closing velocity and small degree of its occurring point in patients with Lock, and long opening and closing phase in patients with MPDS.