The law specifies how a doctor may write a medical certifcate and how a patient or his beneficiaries can obtain his medical records. It's important for a doctor to know this rules. A 56 years old patient was referred to our hospital for pulmonary adenocarcinoma cT2N2M1, the clinical stage was IV. The patient underwent radiotherapy and chemotherapy. During the treatment, the relations with the family were difficult. The patient refuse to accept the doctors tell his son any information and get married with his companion in secret. After patient's death, the son and the wife asked for many medical certificates. The doctors turned down so the son asked for the patient medical records. This observation asks the question of the medical certificates: how and when write them, which are obligatories? Moreover, how should a patient or his beneficiaries obtain medical records?