Abstract
In medical services, the legal connection between doctor and patient is always contractual. The doctor agrees to give medical services to the patient, and the patient agrees to compensate the doctor for those services. However, agreements between doctors and patients are frequently formed orally rather than in writing in medicine. As a result, when a contract is breached and a dispute arises in court, the parties have difficulty demonstrating. The purpose of this study is to examine evidence of contract default in the medical service industry. This study is based on the literature and employs a normative legal research methodology. The analysis was conducted utilizing a conceptual framework, a statutory framework, and a comparative framework. This study suggests that proof of default in a medical service contract dispute can rely on witness statements, admissions, suspicions, and oaths without written evidence. Meanwhile, in terms of the contract's content relating to the doctor's and patient's rights and obligations, it can refer to the relevant provisions of the law, the prevailing customs in the field of medical service, as well as the propriety that must be observed in the execution of the medical service contract.