Osteoarthritis(OA) is a widespread, slowly developing disease with a high prevalence rate increasing with age. The most common big joints involved in OA is the knee, where the disease particulary strikes, causing difficulties in rising from a chair. climbing stairs, kneeling. standing, and walking. The primary complaints of these patients include pain, stiffness. instability, and loss of function. The purpose of this study was to assess the impact of self-reported symptoms and limited flexion, and limited extension on functional impairment in patients with knee osteoarthritis. In the data collection, a total of 206 who had visited the physiotherapy unit at six different departments of orthopedics were interviewed in K City from June to September, 2000. The results of the study summarized are as fellows: 1. There was a significant difference among different degree group of limited flexion(p<0.05). A group difference was demonstrated between <5 ${sim}$ 15 and 16 > (F=16.21, p<0.05). In the relationship between the degree of limited flexion and the level of functional impairment, the h igher the range of limited flexion, the lower the level of functional impairment. 2. In the relationship between the degree of limited extension and the level of functional impairment, a group difference was revealed between the non-limitation group and the <10 and 11 < However, no significant difference was noted between 11 ${sim}$ 20 and 21 >(F= 13.37, p<0.05). In conclusion, finding above suggest that functional impairment is closely correlated with limited tlexion and extenion