Purpose: The purpose of this paper is to determine effects of auricular acupressure on knee pain, range of motion, and sleep in the elderly with knee osteoarthritis. Methods: This is an experimental study designed with randomization and single-blind in a placebo-control approach. The subjects included the elderly with knee osteoarthritis who were using an elderly welfare facility. In each of the groups, 28 subjects were assigned. For the experimental group, auricular acupressure was applied to five pressure points related to the pain caused by osteoarthritis and sleep. In the case of the placebo-control group, auricular acupressure was applied to other five points than the former. The intervention lasted eight weeks. In order to examine intervention effects of auricular acupressure, joint pain, Pressure Pain Thresholds (PPTs), and extension and flexion range of motion (ROM) were measured weekly. As for the preand post-examinations, pain, sleep quality, and the time-by-sleep stage of the patients with knee osteoarthritis were measured. Results: The VAS scores in the experimental group with auricular acupressure significantly decreased through time (p<.001) and WOMAC also significantly decreased (p<.01) compared with the placebo-control group. However, there were no significant differences in PPTs. The flexion (p<.01) and extension (p<.001) ROMs measured for eight weeks improved over time. Meanwhile, sleep quality improved significantly after the intervention termination (p<.01), but there was no significant difference found in the time-by-sleep stage. Conclusion: Auricular acupressure applied for eight weeks was found to be effective in reducing joint pain, improving knee ROM, and improving sleep quality in patients with degenerative knee arthritis.