When facing the problem of dyspnea, patients of motor neuron disease could still expect a long term survival if they choose to accept tracheostomy and artificial ventilation. However, most patients would rather die than be kept alive on machine. Is this choice legally permissible according to the Hospice-Palliative-Care-Law in Taiwan that allows only patients in terminal phase to have the right of DNR? If it is illegal to withhold tracheostomy and artificial ventilation in the above described case, how should the case be morally judged? Is it a form of passive euthanasia? If it is morally acceptable to withdraw tracheostomy, what impacts will it exert upon the Hospice-Palliative-Care-Law? This article deals with all these issues.