Background: The main clinical symptoms of knee osteoarthritis (Knee Osteoarthritis, KOA) include joint pain, stiffness, and dysfunction, which seriously affect the living standards and health of middle-aged and elderly people. Early diagnosis of KOA is helpful for intervention and prevention. Objective: To compare the Bone Marrow Edema (BME) grade and pain grade in KOA patients to explore the correlation between KOA pain and BME imaging changes. Methods: A total of 322 patients with KOA who were diagnosed and treated in the first and third departments of the First People's Hospital of Zunyi City were collected. 285 cases met the inclusion criteria; according to Kellgren-Lawrence (K/L) standard classification, the included patients were divided into low KL group, 190 cases; high KL group, 95 cases, the BME size (damaged The depth is measured perpendicular to the adjacent articular surface) for grading; VAS pain scoring standard is used to divide the pain grade; and the corresponding pain grade data is statistically calculated. Results: 1. In the low K-L group and the high K-L group, the age of the patients is different, and women are lower than men. The incidence of BME in women in the low K-L group was higher than that in men; in the high K-L group, there was no difference in the incidence of BME between men and women in the group. 2. In the low K-L group, BME grade was positively correlated with pain grade. In the low K-L group, the K/L grade was not related to pain. 3 In the high K-L group, BME grade and K/L grade were positively correlated with pain grade. Conclusion: 1. BME and KOA pain grade are positively correlated. 2. In the diagnosis of KOA patients with high pain grades and low K/L grades, the K/L grades are defective.