Quantitative analysis of the impact of digitalization on the energy, environment and economic comprehensive benefits of the energy Internet has important theoretical and practical value. Based on the perspective of industrial chain, this paper adopted the method of System Dynamics theory to describe the key role of digital technology investment in upstream energy production, midstream energy transmission and downstream energy consumption of the energy Internet industry. It identified digital technology investment and other key factors that affect the efficiency of the Energy Internet, clarified their feedback relationships. On this basis, it built a system dynamic model including energy producers, energy service provider and the end user subsystems to quantitatively simulate the comprehensive impacts of the Energy Internet industry under the change of the proportion of different types of digital technology investment. The simulation results show that digital technology investment plays a key role in improving the comprehensive benefits of the energy Internet; Under the scenario of high proportion of digital technology investment, it is estimated that by 2025, digital investment of energy internet will provide nearly 0.72 million jobs for Chinese society every year, and the installed capacity of clean energy power generation will increase to 1.76 billion kilowatts, which can reduce carbon dioxide emissions by 5.7 billion tons in total. Increasing the proportion of digital technology investment can significantly improve the comprehensive benefits of the energy Internet and strongly support the development goals of China's 14th Five Year Plan.