The sensor-cloud is combined with cloud computing and wireless sensor networks, which extends the service ability of WSN by the support of cloud computing. It is one of the hot topics among the current researches. After comparing and surveying the mainstream system adequately, the characteristics and development of sensor-Cloud were summed up. Then, the direct influence of existing trust issues in the system for data protection and application on upper layer were found. The announced reasons explained that existing schemes were difficult to provide trusted sensor-cloud services. This was because that the capabilities of the underlying WSN nodes were too weak, and cloud computing model lacked the direct management of underlying nodes and data and so on. The trusted structures based on fog computing were given, and the key technologies of trusted evaluation, trusted data collection, and trusted storage were designed. Finally, the discussion pointed out new views for the researches in trusted sensor-cloud.