For wireless sensor networks (WSNs), mobile sink is an effective approach to extend network lifetime. In underwater or disconnected network, multi-hop routing mechanism is not applicable because of long transmission delay, high error rate, or disconnected network. Hence, it is necessary to use mobile sinks in order to collect data. In this paper, we consider the problem of collecting data from each sensor into the mobile sinks with energy constraints. We formulate the tour planning of a mobile sink collecting sensor data to the ellipse graph. Our scheme is to minimize the distance of the total tour and the total energy consumption, while satisfying the energy constraint of mobile sinks. Simulation results show that our scheme can effectively collect sensor data.