in various form of policing, it has been pointed that police stop & questioning has critical problems, because although there is a effective aspect related to crime prevention or investigation in police stop, but to the citizens, as they would be felt or treated as latent criminals by policeman, so police stop & questioning has made displeasure or dissatisfaction, still more no-cooperation and hostility against law enforcement. there are three major legal issues in police stop & questioning.; first, how can we distinguish short stop or briefly detain with arrest? second, during police stop, does the detainee have to answer to question by policeman about identification information, and the other information, for example, explanation of person’s action, address, destination, or introducing written identification like driver license, etc. and third. can the policeman do inspection to belongings of detainee, separately search & seizure of criminal procedure. In United States caselaw, namely Terry top, when the detainee was not free to leave from police stop situation, although police stop & question with the condition of reasonable suspicion by policeman is needed as routine policing for efficient crime prevention, it was arrest, not police stop, so illegal if without warrants or probable cause(free to leave test). and it is possible to inspect detainee or his belongings during lawful police stop, but only weapons can be inspected for the sake of safety of policeman or public by means of frisk(stop and frisk). and in relation with the right against self-incrimination, detainee has no obligation to answer the question except merely name as identification information(the Hiibel case law). but it has been insisted strongly in korea with reference of conservative Japanese caselaw and police practice that policeman can restraint detainee to leave during police stop, by physical contact or authority of policeman, because these means are persuasive methods, not coercion or arrest, custody, especially by police and law enforcement practice sides. in this study, the issues of police stop & questioning that are mentioned above will be revisited, expecially with the lower court case related to distinguish lawful short stop with unlawful arrest.