The skin is one of the important organs in the human body because it functions to receive stimuli such as touch, pain and other influences from the outside. According to the data, skin disease is the third out of the ten most diseases in Indonesia and the skin specialists carry out the treatment of patients. However, due to the limitations of the experts resulting in the slow handling of patients so that needed a tool that can help diagnose patients with skin diseases. Case-Based Reasoning is one of the problem-solving techniques to build a system by making decisions from new cases based on the solutions of the old cases that are closest to the new case. The process of diagnosis is to enter new problems, compared to the old case, and then calculate the value of proximity using Minkowski distance. This study produced a case-based reasoning system to diagnose skin diseases due to the virus and bacterial infections based on selecting the symptoms suffered by patients, and providing treatment solutions. The testing is done by comparing the expert diagnosis data and system diagnostic results with 92.10 % accuracy.

Keywords: Case Based Reasoning, Skin Disease, Minkowski Distance.