To assess the efficacy in providing improved function and pain relief by administering 8 weeks of acupuncture as adjunctive therapy to standard care in elderly patients with OA of the knee. This randomized, controlled, blinded trial was conducted on 55 patients with OA of the knee. Forty-one patients completed the study (26 females, 15 males, mean age ± SD 71.7 ± 8.6 years). Patients were randomly divided into an intervention group that received biweekly acupuncture treatment (n = 28) and a control group that received sham acupuncture (n = 27), both in addition to standard therapy, for example, NSAIDS, cyclooxygenase-2 inhibitors, acetaminophen, intra-articular hyaluronic acid and steroid injections. Primary outcomes measures were changes in the Knee Society Score (KSS) knee score and in KSS function and pain ratings at therapy onset, at 8 weeks (closure of study) and at 12 weeks (1 month after last treatment). Secondary outcomes were patient satisfaction and validity of sham acupuncture. There was significant improvement in all three scores in both groups after 8 and 12 weeks compared with baseline (P < .05). Significant differences between the intervention and control groups in the KSS knee score (P = .036) was apparent only after 12 weeks. Patient satisfaction was higher in the intervention group. Adjunctive acupuncture treatment seems to provide added improvement to standard care in elderly patients with OA of the knee. Future research should determine the optimal duration of acupuncture treatment in the context of OA.