In the normative documents of our country, the criminal law and the law of public security administration use the word indecency at the same time. However, whether the meaning of the word indecency is the same in the two normative documents is controversial, which caused the boundary between illegal and criminal acts is very vague. In order to clarify the crime standard and maintain the modesty of the criminal law, we should exclude the subjective factors of the perpetrator and the victim from the objective behavior mode, clarify the scope of indecency in the crime of compulsory indecency, and clarify the specific behavior mode of compulsory means. Because of the wide range and large difference in coercive means and indecent acts, the fixed crime can not meet the needs of the protection of law interests. We should consider classifying behaviors and combine them in different ways to identify the behavior mode of the basic crime.