The invention relates to a publishing and subscribing system and method based on a wireless sensor network and cloud computing. The system comprises a WSNs side, a user side, a bridging side and a cloud side. The bridging side comprises a plurality of filter chains composed of pipelines and filters, and the filter chains can effectively cache data transmitted from the WSNs side and reduce noise in the data. Services applied to the cloud side comprise an IaaS and an SaaS, wherein the IaaS comprises three layers of structures namely a publishing layer, an interaction layer and a subscribing layer, the publishing layer is connected with the filter chains, receives publishing information transmitted by the WSNs side, and the subscribing layer is connected with application software in the SaaS of the cloud side and collects subscribing information of a user and user account information. The interaction layer is connected with the publishing layer and the subscribing layer and receives and matches the publishing information and the subscribing information. The publishing and subscribing system and method can effectively avoid disorder of the publishing information and the subscribing information, automatically match the publishing information and the subscribing information, reasonably link the cloud side and the WSNs side, effectively eliminate the noise of the publishing information, transmit the data to the user in real time and improve accuracy and real-time performance of the data.