Wireless Sensor Network (WSN) is composed of distributed spatially connected sensor nodes with limited computing power and storage. However, Mobile Sink (MS) based Wireless Sensor Networks (WSN) showed great advantage over the traditional WSN for saving energy . By adopting good movement strategy for mobile sink, routing, data gathering and communication policy, MS based WSN can more effectively utilize all the available resources as compared to traditional WSN. On the contrary Cloud Computing provides computing and storage resources typically through the Internet. Therefore, there is a recent trend to combine MS based WSN with the clouds so that both can get benefit from each other. In this chapter, we first give an introduction to Wireless Sensor Networks (WSN), Mobile Sink based WSN and Cloud Computing. After then, we give an overview of state-of-the-art work on Wireless Sensor based Cloud Computing (WSCC). Subsequently, integration of WSN and Cloud Computing is highlighted with some insights on how WSN and Clouds can both get benefits from each other. Applications of Wireless Sensors over the cloud are then described. Afterwards, we explain incorporation of mobile sink between WSN and Cloud. Finally, we discuss issues, challenges, and future directions in the realization of Wireless Sensor Network based Cloud Computing.