Ginger is an effective treatment against nausea and vomiting but there are only a few clinical studies of the effect as an anti-inflammatory or analgesic agent. A double-blind randomized controlled trial of one gram of powdered ginger per day in a capsule compared with a placebo in patients with osteoarthritic knees was carried out. The number of participants in each group was thirty. The length of treatment was eight weeks. The efficacy of the drug was monitored by using the Knee Injury and Osteoarthritis Outcome Score (KOOS). The authors used repeated ANOVA to compare scores between each group. One gram ofpowdered ginger per day did not improve kneejoint pain, symptoms, daily activities, sports activities and quality of life compared with a placebo. Prominent side effects did not occur The systolic and diastolic blood pressure, body mass index and blood chemistry were not changed after receiving treatment. The present study showed that one gram per day of powdered ginger could not relieve joint pain and improve symptoms and the quality of life during eight weeks of-treatment of osteoarthritis of the knee compared with the placebo.