Euthanasia committed even with the patient’s consent and for the good sake of the patient is still considered as a crime because under the Thai criminal law the motive is not an element of crime in such a case. The principle volunti non fit injuria, even if it is not explicitly mentioned in the Criminal Code, is applied in the Thai criminal law with certain reservation. According to Thai Supreme Court’s decisions, the explicit consent of victim in criminal offences, if not contrary to good moral, can constitute an exemption of criminal punishment. However, if the victim’s consent is considered to be contrary to good moral; the person who committed the offence, even though he has the good intention to relieve the victim from his suffering, will be judged guilty of committing an offence against life and body.