Unmanned aerial vehicle (UAV) network is widely applied in the traffic monitoring, remote sensing, search-and-rescue and military reconnaissance, and so on. In this letter, we have addressed the capacity and delay of UAV network with n UAVs that are intended to monitor three-dimensional environment such as air pollution, toxic gas leakage, and so on. We have derived the capacity and delay scaling laws of UAV network with mobility pattern information. Namely, when UAVs return to control station to charge battery, they can assist to deliver data for the UAVs along the returning path with a store-carry-and-forward (SCF) manner. Compared with traditional multi-hop transmission, the capacity of UAV network can be improved Θ((n/(log n))) times and the delay can be reduced Θ(((n/(log n))) ^1/3 ) times. Hence our research may motivate the application of SCF mode in UAV network.