Abstract: In the administrative power spectrum, the main relationship between traffic police power and other administrative power can be expressed as mutual assistance. This definition not only provides legitimate explanation about the not unified contents of the relevant rules and regulations, but also has the justification of its existence in the fact of the dislocation of law norms and law facts and the demands for cooperative urban governance. The establishment of the relationship should follow dual dimensions. Traffic police assistance should have basic condition, authority requirements, passive situation, and the adjudication process. In contrast, the basic condition for other administrative subject assistant behavior should be more broad. The rejection of request for assistance and the responsibility of assistance should stipulate different relief paths.