Total knee prosthesis (TKP); It is a surgical treatment used in the management of functional limitations and severe pain occurring on the degenerated joint surface as a result of rheumatoid arthritis, osteoarthritis, posttraumatic arthritis and other nonspecific arthritis. Nursing care is of great importance in the success of TKP surgery. Reducing pain, preventing complications, increasing self-care ability, and improving the quality of life by improving postoperative knee functions are the main goals of postoperative nursing care. In order to achieve these goals, patients and their relatives need to receive training on home care in the post-operative period before discharge. With the increasing use of mobile technologies in daily life and the increasing adoption of e-health, the opportunity for people to improve their self-management skills through e-health is increasing. Mobile Health (m-Health) provides convenience in many areas such as educating the public, warning about potential diseases and disease risks, and communicating with messages, notifications and video when necessary. It also affects the way nursing services are delivered and provides great benefits in the delivery of nursing services. For all these reasons, it was aimed to examine the effect of mobile application-supported care given to patients with total knee prosthesis on functional status and self-care ability.