In the context of big data, opening government data to society for development and utilization would improve the transparency of government work and promote harmonious social development. Improving the sustainability of open government data (OGD) is an important and challenging issue, and has received the attention of multiple governments. The goals of this study are to construct a new evaluation model for the sustainability of OGD that explores the main influential factors and amends the priorities. We used a combination of the Decision-Making Trial and Evaluation Laboratory (DEMATEL) method and the Analytical Network Process (ANP) method known as DANP to construct an influential network relationship map (INRM) of the evaluation system and calculate the criterion weights. The INRM and weights can help decision makers understand the complex assessment system and set priorities for improving OGD. The results demonstrate that the improvement priorities of dimensions have the following order: impact (D4), use (D3), data (D2), and environment (D1). Economic, social, and political values are the three critical factors for improvement of the sustainability of OGD. Some implications for management are also provided.