At present, narcotic crime is the major problem of the nation and from the statistics of criminal procedure to these narcotic criminals, it shows that the number is above 60% of the total crimes. Consurrently, the law enforcement and evidence searching to punish these criminals are not successful enough to get closer to the main leaders due to the lack of evidence. Plea bargaining has then become the methodology for evidence searching of the drug enforcer. By means of enforcer's negotiations with the defendants for plead guilty and co-operation, the enforcer can reduce or adapt the charges or suggest an appropriate charges to the court but still based on the original charges. When plea bargaining is used in the narcotic cases, the state can effectively find the evidence to impose the law against the principal and the belonging relating to the case. At the same time, the defendant would have the chance to change their mind and turning to co-operate with the drug enforcer thus would get a lower punishment and a chance to get back into the societies. This bargaining will be used efficiently only when the defendant has been totally protected by the law and decided to accept the bargaining and co-operate with the drug enforcer which would not be considered to transgress the rights of the defendant, and also adjustment of law relating to evidence hearing and rule in narcotic case.