Euthanasia which means; the killing of the patient who has disease impossible to be cured regarding to current medical parameters and causes severe pain or it means leaving the patient to dead by ceasing the medical attention, is a notion involves several disciplines such as law, ethic and religion. Euthanasia has different types with regard to the action that causes the death and with regard to its actualization by the will of the patient. Therefore in our work, euthanasia is presented comprising the historical process affected this notion and its types are analyzed by discussing the explanatory examples. Our work includes the issues as the determining factors of the euthanasia, whether the right to life which is the most fundamental personal right is an obligation and whether right to life simultaneously makes people possess "the right to die". In this sense, we investigated the view of primary legal systems regarding the notion of euthanasia and whether they considered this as a right and gave permission to its actualization. The work also includes the perspective of religions as one of the most important factors of the legal systems regarding this issue