[Purpose] The purpose of this study was to determine the effects of nerve mobilization applied in conjunction with electromagnetic diathermy, in patients with lower back pain. [Subjects] Twenty-two subjects with lower back pain participated in this study. They had had chronic pain in the lower back area for over six months. [Methods] The subjects were selected based on selection criteria, and randomly divided into two groups. The experimental group (n=11) were given electromagnetic diathermy in conjunction with nerve mobilization to patients. The control group (n=11) were applied with only electromagnetic diathermy. [Results] The Oswestry Disability Index, location of symptom scale and knee joint extensor strength showed significant improvements in the experimental group and control group after the intervention. [Conclusion] Nerve mobilization applied in conjunction with electromagnetic diathermy was more effective at improving function and strength, than nerve mobilization alone.