Abstract:[Objective] To explore the correlation between pain symptoms and imaging grades in knee osteoarthritis. [Methods] A total of 285 patents who visited in out-patient department for knee osteoarthritis in our hospital were included in this study. The patients aged from 44 to 61 years, including 107 males and 178 females, with the course of disease ranging from 2 to 8 months. The correlations between pain symptoms and clinical and imaging grading parameters were analyzed. [Results] The patients with mild pain were significantly elder (P<0.05) , of male dominated (P<0.05) , shorter course of disease (P<0.05) , higher HSS score, less extent of genu in terms of femorotibial angle (FTA) and medial proximal tibial angle (MPTA), higher Kellgren-Lawrence (K-L) grade in X-ray films (P<0.05) and lower bone mar- row edema (BME) grade on MRI than those with severe pain. However, there were no statistically significant differences in the main symp- tom side and body mass index (BMI) between the two groups (P>0.05) . As results of Spearman correlation analysis, there was a significant- ly negative correlation between VAS score and K-L grade (P<0.05) , whereas there was a significant positive correlation between VAS score and BME grade (P<0.05) . There was no a correlation between K-L grade and BME grade (P>0.05) . In term of multiple linear stepwise re- gression, the HSS (β=-0.736, P<0.001) and the age (β=-0.123, P=0.002) were negatively correlated with VAS score. [Conclusion] The BME revealed by MRI has a positive correlation with pain symptoms.