The second Space Information Networks academic forum will be held at August 9-10, 2018, in Changchun, Jilin. The forum is hosted by Department of Information Science, National Natural Science Foundation of China together with the panel of guiding experts of Space Information Networks major research plan, organized by Posts & Telecom Press. Academician Quan Yu, Academician Jianhua Lu, Academician Bangkui Fan, Academician You He and Professor Ping Zhang as well as other authoritative experts will be specially invited to the forum. At the same time, specialists, scholars and students of the filed are welcomed to contribute. We kindly remind you that submission deadline is at May 30.