This paper follows a normative research methodology of law, and will combine through a collaboration with business economic approach in the analyze process in order to expose the opportunity of conducting money laundering through cash courier. The proper detection mechanism of cash courier will plays an important role to prevent money laundering. There are two mechanisms that use in cash courier, declaration system and disclosure system. In some countries, which are using custom declaration as its mechanism will lie on the honesty of person. The mechanism of treating cash courier in money laundering and considering whether it is an administrative violation, or a criminal violation, or a civil violation will be important to be criticized. It should be reconsidered that cash courier in money laundering is a crime, thus should not put it as merely an administrative scope of violation. The administrative sanction would not be proper to handle it. The problem of cash courier would not be a simple problem to be solved. It needs ideal concept and framework to be constructed which is based on objective methods for what law can do to handle, and further will assist to prevent and eradicate money laundering. This qualitative research paper that follows content analysis method provides better insight into cash courier in money laundering and the role to be ensured in detecting mechanisms.