Background Patients’ perceptions and beliefs of disease could be influenced by their lifestyle and culture. Although it is important to understand their perceptions and beliefs toward disease to prevent and manage osteoarthritis (OA) through conservative care, this topic has not been investigated in Japanese people with knee OA. Therefore, this qualitative study aims to clarify how Japanese patients with knee OA experience and perceive their symptoms and disabilities, and how they face them during conservative care.Methods Participants were recruited by purposive sampling. Face-to-face, semi-structured interviews were conducted with nine patients (2 men and 7 women, mean age, 74.3±5.5 years) with knee OA until data saturation was reached. Interview data comprised participants’ accounts of particular personal experiences of living with knee OA, including their perceptions and attitudes toward knee OA-related symptoms and disabilities. Two physiotherapists (one with extensive experience conducting qualitative studies) and four physiotherapy students conducted the interviews. Recorded interview data were transcribed verbatim in Japanese. Data analysis, including developing a coding scheme, was conducted based on a grounded theory approach. Results Six categories were extracted from the data: “self-analysis on the cause of knee OA,” “difficulties in daily life due to knee symptoms,” “psychological barrier,” “how to deal with knee pain and difficulty in moving,” “importance of connecting with others,” and “information considered useful to cope with knee OA.” Japanese patients with knee OA desired evidence-based information and to connect with other people in the same situation to solve problems related to their condition. Conclusions To address patients’ concerns, medical professionals should carry out careful interviews and obtain information regarding patients’ past experiences, and understand their experiences related to knee OA. Symptoms and difficulties experienced by patients with knee OA should be managed by evidence-based information integrating their perceptions and beliefs toward knee OA.