The invention belongs to the technical field of the Internet of Things, and discloses a multi-domain hierarchical multi-domain Internet of Things platform and a multi-domain management method. The multi-domain hierarchical multi-domain Internet of Things platform comprises: a cloud platform multi-domain management center module used for monitoring a load condition and an operation state of a cloud platform sub-center module in real time; and the cloud platform sub-center module used for registering other cloud platform sub-centers and managing data access and command issuing authority. According to the multi-domain hierarchical multi-domain Internet of Things platform disclosed by the invention, the cloud platform multi-domain management center monitors the cloud platform sub-centers in real time, and when a certain cloud platform sub-center cannot work normally, the cloud platform multi-domain management center intercepts and records an interactive request with the cloud platform sub-center; the Internet of Things platform is divided into multilevel domains, an upper level domain manages a plurality of lower level domains, the upper level domain and the lower level domains perform direct interaction, the domains at the same level can directly perform data interaction, the domains at the same level can perform signaling interaction after being forwarded by the upper level domain, and the authorization information of all domains is shared; and when multi-domain cloud platforms perform networking again after network outage, the platforms have automatic registration functions.