This study evaluates the efficacy and safety of TongBi capsule compared with placebo in the treatment of knee osteoarthritis in adults.Half of participants will receive TongBi capsule in combination,while the other half will receive a Placebo.

Inclusion Criteria:

1.45-75 years of age (including 45 years and 75 years old), men and women are not limited.

2. western medicine diagnosis of knee osteoarthritis, clinical classification for primary.

3.The severity of the imaging classification of K-L≤Ⅲ; 4. treatment VAS pain scores than 40mm (select the subjects most obvious limb pain symptoms).

5. informed consent form signed by the patient or legal representative.

Exclusion Criteria:

1. within 3 months prior to the trial, the patients were treated within intra-articular treatment.

2. 4 weeks before the treatment, corticosteroids, non steroidal drugs, intra-articular injections or other drugs to improve the condition (such as cartilage protective agents) were used.

3. The screening period has any disease history or evidence:

   The basic of serious cardiovascular and cerebrovascular diseases; An active, recurrent peptic ulcer or other hemorrhagic disease risk; Sales and other serious diseases of digestive system; An associated with malignant tumors, blood, or other serious diseases or system; Patients who are unable to cooperate or cooperate with other mental disorders.

4. Before the screening, any laboratory test indicators meet the following standards:

   An admission of liver and kidney function showed that ALT and AST is more than 1.5 times the upper limit of the normal value, Cr is more than 1.2 times the upper limit of normal (Reference Research Center laboratory where the range of normal value); An other clinically significant laboratory abnormalities, and the researchers judged not into the group.

5. Allergic constitution or allergic to TongBi capsul, excipients or similar ingredients;

6. Professional athletes;

7. doubt or indeed history of alcohol and drug abuse;

8. participants who participated in other clinical trials within the first 3 months;

9. the researchers believe that patients should not participate in this clinical trial.