As one of the most significant parts of “Internet +”, Internet of things (IoT) is being widely applied in various aspects of human society. IPv6 identification is the base of large-scale deployment and interconnection of IoT. Nevertheless, the 128-bit IPv6 address brings more storage and bandwidth consumptions for resource-constrained IoT. A novel compression mechanism-named IACH is proposed for the hierarchical IoT forwarding architecture, which mainly includes: removing invalid routing message at the end of IPv6 address, address stripping, and address extension. Moreover, the irregular outside IPv6 addresses can be translated into virtual addresses of IoT subnets by means of address mapping, which is compressed according the described mechanism. IACH is fully compatible with 6LoWPAN. Experiments and performance analysis show that IACH can significantly increase the real upper payload in packets transmission. In particular, the forwarding delay of IACH is shorter than standard 6LoWPAN for packets with the same length of IP-upper payload.