Abstract: Objective?To determine the effect of elastic taping on patients with patellofemoral pain and its impact on the onset time of vastusmedialis and vastuslateralis. Methods?Eligible patients were assigned into the treatment and control groups randomly. Patients in the treatment group received a 5-day taping with therapeutic stretch. Patients in the control group were give placebo taping without therapeutic stretch. Ultrasound therapy was applied to all of the participants as a basic treatment. The levels of pain and surface electromyography were evaluated before treatment, after the first taping and on the 6^th day (without taping). Results?Patients in the treatment group experienced immediate improvement in pain and onset time of vastusmedialis and vastuslateralis compared with the controls. On the 6^th day (without taping), further improvement was achieved in pain and onset time of vastusmedialis and vastuslateralis in the treatment group compared with the controls (P<0.05). Conclusion ?Elastic taping can effectively improve pain and onset time of vastusmedialis and vastuslateralis.