This essay is to discuss the definition and problems of homeless from the perspective of police and order law. According to German police theory, homeless may put public safety and order in danger. On the other side, the self-esteem and people's right of homeless may be hurt. Both situations shall be removed by the efficacious action of police administration. Thus, the police actions to homeless are the key point in this essay. Most of the police actions to homeless are defined in the law of the homeless (the law of social relief or the rules of the homeless in country and town). Based on the history, constitution, central laws and local laws, this essay tries to solve the problem of the homeless and to protect people's right in constitution. Because little research has been done to discuss the law of the homeless, this essay adopts German literature and above-mentioned theories. Also, this essay examines the rules and administrative actions of homeless and provides suggestions for the law of homeless. There are few cases of court for the homeless in Taiwan, thus this essay only comments daily case in the view of law and provides some consultations in executions for the administrations.