The invention discloses an elevator audio advertisement injecting system based on an internet of things. The elevator audio advertisement injecting system comprises an advertisement cloud platform, afog computing terminal and an edge terminal, wherein the advertisement cloud platform is arranged at a cloud terminal and used for collecting, unloading and managing advertisements of advertisement owners, distributing advertisement injecting for the fog computing terminal, receiving and counting advertisement playing distribution uploaded by the fog computing terminal, accordingly providing advertisement playing information forms as a reference for the advertisement owners and feeding back information for injecting, the fog computing terminal is arranged at a community property management terminal and comprises a fog computing module, an advertisement storage module, an edge terminal connection module and a local management module, and the edge terminal comprises a safety monitoring device, an elevator parameter collector and an audio player which are mounted in an elevator. The elevator audio advertisement injecting system has the advantages that cost is saved, the advertisement owners directionally perform local advertisement injecting, the advertisements can be pushed in a classified manner according to different people, and the like.