Purpose : The purpose of study was to better understand the effects of Interferential Current (IFC) and Ultrasound on the ROM and pain in patients with chronic back muscle pain. Methods : Twenty patients with chronic back pain were randomly assigned to IFC stimulation groups and Ultrasound stimulation groups. Both groups used the same method for 20 minutes each session, three times a week for 4 weeks at the same time point and with the same amount of treatment. Measurement items are visual analogue scale (VAS) and range of motion (ROM). Results : This study showed that the IFC stimulation group and the ultrasound stimulation group demonstrated significant improvement in ROM increase and pain reduction. Both groups showed a significant reduction in VAS; however, the ultrasound stimulation group decreased more than ultrasound stimulation group. And, both groups showed a significant increase in ROM. The ultrasound stimulation group increased significantly more than the IFC stimulation group in ROM of flexion and extension. The IFC stimulation group increased significantly more than the ultrasound stimulation group in ROM of lateral flexion. Conclusion : Pain relief was more effective in the ultrasound group. The ultrasound showed a more significant effect than IFC in ROM of flexion and extension. The IFC showed a more significant effect than ultrasound in ROM lateral flexion. The results of this study suggest that the treatment effects are different on patients with chronic back pain, according to treatment methods.