Objective: The purpose of this study was to examine how rehabilitation and patient education for knee osteoarthritis improves health-related quality of life (HRQOL) and to identify factors influencing HRQOL. Methods: Between May 2020 and March 2022, 30 patients with osteoarthritis of the knee were treated conservatively and rehabilitated with a patient education program. The patient education program was based on the health belief model by Sedlak et al., and patient education using pamphlets was provided during the rehabilitation intervention. The survey items were patient basic information, instrumental activities of daily living (ADL) (FAI), fear of falling (FES), degree of depression (GDS), HRQOL (SF-8), knee function assessment (JOA score), and X-ray classification (K-L classification), and the survey method was a self-administered questionnaire at the start of rehabilitation, 1 month after the intervention, and at the end of the rehabilitation intervention. We examined factors affecting the physical component summary (PCS) and mental component summary (MCS) of HRQOL scores. Results: JOA score, FES, FAI, GDS, and SF-8 improved significantly (p<0.01). MCS was also negatively correlated with FES and age (r=-0.486, -0.368). Sex was extracted as a factor for PCS as a factor affecting HRQOL (p<0.01). MCS was extracted with FES as a factor (p=0.046). Conclusion A rehabilitation intervention incorporating patient education in osteoarthritis of the knee showed improvement in HRQOL and may be useful for improving depression, fear of falling, and instrumental ADL.